On Authentication Timeout - Save Web Form Contents

10. June 2010
Comments (1)

I was working on a project recently where I had to figure out how to persist user data in a web form after their Forms Authentication session as expired.

So I was thinking of ways to do this as I searched the know all Google. Walla!  Someone's already had to do this, why invent the wheel.  Found a post by Peter Ravnholt, on the MSDN site. http://code.msdn.microsoft.com/formsaver 

He Implements the HttpModule and handles saving the form state on FormAuthentication events. Really neat idea.  I tried is code, now keep in mind I'm doing this for Visual Basic, so I manually converted it all, but I couldn't get it work. Maybe I was converting something wrong.  I was getting "The state information is invalid for this page and might be corrupted."

Well RichardDeeming in the discussions for this post had an updated version that worked a little better then the original. http://code.msdn.microsoft.com/formsaver/Thread/View.aspx?ThreadId=88  Thanks to his code, I converted it to VB.Net and walla!  My pages now handle web content.

I'll post the converted VB version below. 

Thanks Richard and Peter if you ever find your names on here via Google :p

This is my VB version o the FormSaverHttpModule with Richard's changes.  I've modified it a bit since but this works.

Imports Microsoft.VisualBasic
Imports System.Security.Principal
Imports System.IO
Imports System.Web.Configuration
Imports System.Security.Permissions
 
''' <summary>
''' FormSaverModule Version 1.0
''' -Mastro:  Not my orignal idea, found this in use out on MSDN site. I manually converted it to VB
''' as the orignaly is in C#. No comments, so I'll add my own.
''' 
''' This class will handle every new request coming in and PostMapRequest. 
''' If user has Forms Authentication has timed out, class will save the state of the form into cache
''' with a Unique ID of that state to the user's cookie. 
''' 
''' When user logs back in, this class will check if they have the cookie set, if so it will then 
''' load that state back to their page and load the webcontent by generating a runtime transit page that
''' post submits the data back to the destination page and pre-fills in the values.
''' </summary>
''' <remarks></remarks>
<AspNetHostingPermission(SecurityAction.LinkDemand, Level:=System.Web.AspNetHostingPermissionLevel.Minimal)> _
<AspNetHostingPermission(SecurityAction.InheritanceDemand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public Class FormSaverHTTPModule
    Implements IHttpModule
 
#Region "Private Variables"
 
    Private Const CookieName As String = "#FormStateSaverModule/FormRestoreId"
    Private Shared ReadOnly StateCacheDuration As TimeSpan = TimeSpan.FromMinutes(40)
    Private Shared ReadOnly _AnonymousUser As IPrincipal = New GenericPrincipal(New GenericIdentity(String.Empty), Nothing)
    Private _FormsCookieName As String
    Private _LoginUrl As String
 
#End Region
 
    ''' <summary>
    ''' This class is required from the IHttpModule contract
    ''' </summary>
    ''' <remarks></remarks>
    Public Sub Dispose() Implements System.Web.IHttpModule.Dispose
 
    End Sub
 
    ''' <summary>
    ''' This is the first method to run on application start
    ''' </summary>
    ''' <param name="Context"></param>
    ''' <remarks></remarks>
    Public Sub IHttpModuleInit(ByVal Context As HttpApplication) Implements System.Web.IHttpModule.Init
        Me.Init(Context) 'Lets call our Init and send the Application state along with it
    End Sub
 
    ''' <summary>
    ''' We call this Init Method from the IHttpModuleInit and send it the Application State
    ''' and then turn on Events to capture
    ''' </summary>
    ''' <param name="Context">Hold's the Application State</param>
    ''' <remarks></remarks>
    Protected Overridable Sub Init(ByVal Context As HttpApplication)
        If Context Is Nothing Then
            Throw New ArgumentNullException("context")
        End If
 
        _LoginUrl = FormsAuthentication.LoginUrl 'Store the Login page name
        _FormsCookieName = FormsAuthentication.FormsCookieName 'Store the Forms Authentication Cookie Name
 
        If Not String.IsNullOrEmpty(_LoginUrl) Then 'If LoginUrl Exists....
            Dim index As Integer = _LoginUrl.IndexOf("?"c) 'Search for a ? for query string
            If -1 <> index Then 'If ? was found....
                _LoginUrl = _LoginUrl.Substring(0, index) 'Grab the first part of the URL before the ? and set LoginUrl
            End If
        End If
 
        'Add Handlers that now raise events on every Application BeginRequest... and Application PostMapRequest
        AddHandler Context.BeginRequest, New EventHandler(AddressOf Application_BeginRequest)
        AddHandler Context.PostMapRequestHandler, New EventHandler(AddressOf Application_PostMapRequestHandler)
 
    End Sub
 
    ''' <summary>
    ''' A Delegate receiver method for the Application.BeginRequest Event
    ''' </summary>
    ''' <param name="sender">Object</param>
    ''' <param name="e">EventArgs</param>
    ''' <remarks></remarks>
    Protected Overridable Sub Application_BeginRequest(ByVal sender As Object, ByVal e As EventArgs)
        Dim application As HttpApplication = DirectCast(sender, HttpApplication)
        Dim context As HttpContext = application.Context
 
        Dim cookie As HttpCookie = context.Request.Cookies(CookieName)
        If cookie IsNot Nothing AndAlso Not String.IsNullOrEmpty(cookie.Value) Then 'If Cookie exist and has value....
            Dim state As FormState = FormState.Load(cookie.Value) 'Lets try and load the state via the CookieID
 
            'Lets see if the State is valid now that it's loaded and it's originaly location matches where the user is trying to go
            If state IsNot Nothing AndAlso String.Equals(state.Path, context.Request.Path, StringComparison.OrdinalIgnoreCase) Then
                FormState.SetCurrent(context, state) 'State is valid and it's for this request so lets create the object of the state to be used later by Application_PostMapRequestHandler
                Return
            End If
        End If
 
        If IsPost(context) AndAlso Not IsAccessingLoginPage(context, _LoginUrl) Then 'If user is doing a Post back and it's not to the login page...
            cookie = context.Request.Cookies(_FormsCookieName) 'Load Authenication cookie
            If cookie IsNot Nothing Then
                Try
                    Dim ticket As FormsAuthenticationTicket = FormsAuthentication.Decrypt(cookie.Value)
                    If ticket IsNot Nothing AndAlso ticket.Expired AndAlso Not HasAnonymousAccess(context) Then 'If the user has expired.....
                        Dim state As FormState = FormState.Create(context) 'Store current state into cache
                        If state IsNot Nothing Then
                            cookie = New HttpCookie(CookieName, state.StateId) 'save cache ID into user's cookie
 
                            cookie.HttpOnly = True
                            context.Response.Cookies.Add(cookie)
                        End If
                    End If
                Catch generatedExceptionName As ArgumentException
                End Try
            End If
        End If
    End Sub
 
    Protected Overridable Sub Application_PostMapRequestHandler(ByVal sender As Object, ByVal e As EventArgs)
        Dim application As HttpApplication = DirectCast(sender, HttpApplication)
        Dim context As HttpContext = application.Context
 
        Dim state As FormState = FormState.GetCurrent(context) 'Get the context from the cache if it's there
        If state IsNot Nothing AndAlso state.Form IsNot Nothing AndAlso 0 <> state.Form.Count Then 'if the context was there....
            context.Handler = New FormStateSaverHandler(state) 'Then load the runtime transit page and post it back to destination page
        End If
    End Sub
 
    ''' <summary>
    ''' Returns Boolean if request is a Post request to page.
    ''' </summary>
    ''' <returns></returns>
    ''' <remarks></remarks>
    Protected Shared Function IsPost(ByVal context As HttpContext) As Boolean
        Return String.Equals("POST", context.Request.HttpMethod, StringComparison.OrdinalIgnoreCase)
    End Function
 
    ''' <summary>
    ''' Return Boolean after it checks to see if content matches the LoginURL. Basically is the user 
    ''' going to the login page.
    ''' </summary>
    ''' <returns></returns>
    ''' <remarks></remarks>
    Protected Shared Function IsAccessingLoginPage(ByVal context As HttpContext, ByVal loginUrl As String) As Boolean
        Dim result As Boolean = False
        If Not String.IsNullOrEmpty(loginUrl) Then
            If String.Equals(context.Request.Path, loginUrl, StringComparison.OrdinalIgnoreCase) Then
                result = True
            ElseIf -1 <> loginUrl.IndexOf("%"c) Then
                Dim temp As String = HttpUtility.UrlDecode(loginUrl)
                If String.Equals(context.Request.Path, temp, StringComparison.OrdinalIgnoreCase) Then
                    result = True
                Else
                    temp = HttpUtility.UrlDecode(loginUrl, context.Request.ContentEncoding)
                    If String.Equals(context.Request.Path, temp, StringComparison.OrdinalIgnoreCase) Then
                        result = True
                    End If
                End If
            End If
        End If
 
        Return result
    End Function
 
    ''' <summary>
    ''' Returns Boolean if the destination URL in question has anonymouse access.
    ''' </summary>
    ''' <param name="context"></param>
    ''' <returns></returns>
    ''' <remarks></remarks>
    Protected Shared Function HasAnonymousAccess(ByVal context As HttpContext) As Boolean
        Return UrlAuthorizationModule.CheckUrlAccessForPrincipal(context.Request.Path, _AnonymousUser, context.Request.HttpMethod)
    End Function
 
    ''' <summary>
    ''' This class becomes the actual FormState the user was on and is Serialzied and then saved 
    ''' </summary>
    ''' <remarks></remarks>
    <Serializable()> _
    Protected NotInheritable Class FormState
        Private Shared ReadOnly FormRestoreKey As New Object()
 
        Private ReadOnly _id As String
        Private ReadOnly _path As String
        Private ReadOnly _form As NameValueCollection
 
        Private Sub New(ByVal id As String, ByVal path As String, ByVal form As NameValueCollection)
            _id = id
            _path = path
            _form = form
        End Sub
 
        Public ReadOnly Property StateId() As String
            Get
                Return _id
            End Get
        End Property
 
        Public ReadOnly Property Path() As String
            Get
                Return _path
            End Get
        End Property
 
        Public ReadOnly Property Form() As NameValueCollection
            Get
                Return _form
            End Get
        End Property
 
        ''' <summary>
        ''' Loads the state that was set by Setcurrent and tries to return it as a FormState object.
        ''' Returns nothing if it's invalid.
        ''' </summary>
        ''' <param name="context"></param>
        ''' <returns></returns>
        ''' <remarks></remarks>
        Public Shared Function GetCurrent(ByVal context As HttpContext) As FormState
            If context Is Nothing Then
                Return Nothing
            End If
            Return TryCast(context.Items(FormRestoreKey), FormState)
        End Function
 
        ''' <summary>
        ''' Takes the state sent and creates a valid formstate object
        ''' </summary>
        ''' <param name="context"></param>
        ''' <param name="state"></param>
        ''' <remarks></remarks>
        Public Shared Sub SetCurrent(ByVal context As HttpContext, ByVal state As FormState)
            If context IsNot Nothing Then
                context.Items(FormRestoreKey) = state
            End If
        End Sub
 
        ''' <summary>
        ''' Takes the Context of the current Request Form and stores it into Cache with a Unique ID
        ''' </summary>
        ''' <returns></returns>
        ''' <remarks></remarks>
        Public Shared Function Create(ByVal context As HttpContext) As FormState
            Dim result As FormState = Nothing
            If context IsNot Nothing AndAlso context.Request.Form IsNot Nothing AndAlso 0 <> context.Request.Form.Count Then
                Dim id As String = Guid.NewGuid().ToString()
                result = New FormState(id, context.Request.Path, context.Request.Form)
                HttpRuntime.Cache.Add("FormStateSaver_" + id, result, Nothing, Cache.NoAbsoluteExpiration, StateCacheDuration, CacheItemPriority.Normal, _
                Nothing)
            End If
            Return result
        End Function
 
        ''' <summary>
        ''' Loads the Context stored in Cache using the Unique ID
        ''' </summary>
        ''' <param name="id">Unique GUID</param>
        ''' <returns></returns>
        ''' <remarks></remarks>
        Public Shared Function Load(ByVal id As String) As FormState
            Dim result As FormState = Nothing
            If Not String.IsNullOrEmpty(id) Then
                result = TryCast(HttpRuntime.Cache("FormStateSaver_" + id), FormState)
            End If
 
            Return result
        End Function
 
        ''' <summary>
        ''' Deletes the stored Context from Cache
        ''' </summary>
        ''' <remarks></remarks>
        Public Sub Delete()
            HttpRuntime.Cache.Remove("FormStateSaver_" + _id)
        End Sub
    End Class
 
    ''' <summary>
    ''' This class is responsible for generating the Transit page on the fly. 
    ''' Basically a page that loads all the values then submits them back to the destination
    ''' page with the previous viewstate settings so that the form reloads the controls to where
    ''' they were prior.
    ''' 
    ''' This page quickly shows when the user is logging back in and loading a previous web form.
    ''' 
    ''' </summary>
    ''' <remarks></remarks>
    Protected Class FormStateSaverHandler
        Implements IHttpHandler
 
        Private ReadOnly _state As FormState
 
        Public Sub New(ByVal state As FormState)
            _state = state
        End Sub
 
        Protected ReadOnly Property FormState() As FormState
            Get
                Return _state
            End Get
        End Property
 
        Public ReadOnly Property IsReusable() As Boolean Implements IHttpHandler.IsReusable
            Get
                Return False
            End Get
        End Property
 
        Public Overridable Sub ProcessRequest(ByVal context As HttpContext) Implements System.Web.IHttpHandler.ProcessRequest
            Try
                Using writer As HtmlTextWriter = CreateHtmlTextWriter(context.Response.Output, context.Request.Browser)
                    Me.Render(writer)
                End Using
            Finally
                _state.Delete()
            End Try
        End Sub
 
        Protected Overridable Sub Render(ByVal writer As HtmlTextWriter)
            writer.RenderBeginTag(HtmlTextWriterTag.Html)
            writer.RenderBeginTag(HtmlTextWriterTag.Head)
            writer.RenderBeginTag(HtmlTextWriterTag.Title)
            writer.Write("Restoring form")
            writer.RenderEndTag()
            ' TITLE 
            writer.RenderEndTag()
            ' HEAD 
            writer.AddAttribute("onload", "document.forms[0].submit();")
            writer.RenderBeginTag(HtmlTextWriterTag.Body)
 
            writer.AddAttribute("method", "post")
            writer.RenderBeginTag(HtmlTextWriterTag.Form)
 
            Dim form As NameValueCollection = Me.FormState.Form
            For Each name As String In form.Keys
                RenderHiddenField(writer, name, form(name))
            Next
 
            'writer.AddAttribute(HtmlTextWriterAttribute.Align, "center")
            'writer.RenderBeginTag(HtmlTextWriterTag.P)
            'writer.Write("You should be redirected in a moment.")
            'writer.WriteFullBeginTag("br")
            'writer.Write("If nothing happens, please click ")
            'RenderSubmitButton(writer, "Submit")
            'writer.RenderEndTag()
            ' P 
            writer.RenderEndTag()
            ' FORM 
            writer.RenderEndTag()
            ' BODY 
            writer.RenderEndTag()
            ' HTML 
        End Sub
 
        Protected Shared Sub RenderHiddenField(ByVal writer As HtmlTextWriter, ByVal name As String, ByVal value As String)
            writer.AddAttribute(HtmlTextWriterAttribute.Type, "hidden")
            writer.AddAttribute(HtmlTextWriterAttribute.Name, name)
            writer.AddAttribute(HtmlTextWriterAttribute.Value, value)
            writer.RenderBeginTag(HtmlTextWriterTag.Input)
            writer.RenderEndTag()
            ' INPUT 
        End Sub
 
        Protected Shared Sub RenderSubmitButton(ByVal writer As HtmlTextWriter, ByVal text As String)
            writer.AddAttribute(HtmlTextWriterAttribute.Type, "submit")
            writer.AddAttribute(HtmlTextWriterAttribute.Value, text)
            writer.RenderBeginTag(HtmlTextWriterTag.Input)
            writer.RenderEndTag()
            ' INPUT 
        End Sub
 
        Protected Shared Function CreateHtmlTextWriter(ByVal writer As TextWriter, ByVal browser As HttpCapabilitiesBase) As HtmlTextWriter
            If browser Is Nothing Then
                Return New HtmlTextWriter(writer)
            End If
            Return browser.CreateHtmlTextWriter(writer)
        End Function
 
 
    End Class
 
 
End Class
 
 
 
 
 

 

Update: 6/10/10

Here is the original post, and it was moved to codeplex here.  Thanks Peter Revnholt!

.Net Framework, ASP.NET, Programming, VB.NET , , , , , , , ,

hexadecimal value 0x00 is an invalid character

20. April 2010
Comments (0)

This is usually an encodnig issues. Invalid characters in the string going into the xml. Remedy this by converting your string data into UTF8 when assining the data to your XML element.

Example:

XRecordDetail = New XElement(Header, System.Text.Encoding.UTF8.GetBytes(OriginalDataString))

Or

XMLData = XMLSystem.Text.Encoding.UTF8.GetBytes(OriginalDataString)

VB.NET

Some New VB.NET 10 (VS2010) Features

6. April 2010
Comments (0)

 

Autoimplemented Properties (yes C# already had this)

Previous VB.Net 9 (Or VS 2008)

    Private _Name As String
    Public Property Name() As String
        Get
            Return _Name
        End Get
        Set(ByVal value As String)
            _Name = value
        End Set
    End Property

    Private _Addresses As List(Of Car)
    Public Property Addresses() As List(Of Car)
        Get
            Return _Addresses
        End Get
        Set(ByVal value As List(Of Car))
            _Addresses = value
        End Set
    End Property

New VB.Net 10 (Or VS 2010)

Public Property Name() As String

Public Property AddressList() As List(Of Car) = New List(Of Car)

Or (Setting a Default Value)

Public Property Name() As String = "Fred"

Public Property Addresses() As New List(Of Car)

 

Collection Initializers:

 

Public Property Cars As New List(Of Car) from {
                                                New Car With (.Color = “Red", .Make = "Ford"),
                                                New Car With (.Color = “Blue", .Make = "Mazda")
                                              }
 

 

Implicit Line Continuation:

 

No more need for the underscore _ to continue a VB line. You can see from code sample above and from this. 

    Dim Statement As String = "Hello"
        & "World"
        & " All Considered One Line"

 

Watch Video: http://msdn.microsoft.com/en-us/vbasic/ee681550.aspx

VB.NET

VB.NET to C# Differences

11. March 2010
Comments (0)

Found this great link today by Dr. Frank McCown over at Harding University Computer Science Dept from 2009.

http://www.harding.edu/fmccown/vbnet_csharp_comparison.html

 

VB.NET

Program Structure

C#

Imports System
Namespace Hello
   Class HelloWorld
      Overloads Shared Sub Main(ByVal args() As String)
         Dim name As String = "VB.NET"
'See if an argument was passed from the command line
          If args.Length = 1 Then name = args(0)
          Console.WriteLine("Hello, " & name & "!")
      End Sub
   End Class
End Namespace

using System;
namespace Hello {
   public class HelloWorld {
      public static void Main(string[] args) {
         string name = "C#";
// See if an argument was passed from the command line
         if (args.Length == 1)
            name = args[0];
         Console.WriteLine("Hello, " + name + "!");
      }
   }
}

VB.NET

Comments

C#

' Single line only
REM Single line only
''' <summary>XML comments</summary>

// Single line
/* Multiple
    line  */
/// <summary>XML comments on single line</summary>
/** <summary>XML comments on multiple lines</summary> */

VB.NET

Data Types

C#

Value Types
Boolean
Byte, SByte
Char
Short, UShort, Integer, UInteger, Long, ULong
Single, Double
Decimal
Date

Reference Types
Object
String

Initializing
Dim correct As Boolean = True
Dim b As Byte = &H2A   'hex
Dim o As Byte = &O52   'octal
Dim person As Object = Nothing
Dim name As String = "Dwight"
Dim grade As Char = "B"c
Dim today As Date = #12/31/2007 12:15:00 PM#
Dim amount As Decimal = 35.99@
Dim gpa As Single = 2.9!
Dim pi As Double = 3.14159265
Dim lTotal As Long = 123456L
Dim sTotal As Short = 123S
Dim usTotal As UShort = 123US
Dim uiTotal As UInteger = 123UI
Dim ulTotal As ULong = 123UL

Type Information
Dim x As Integer
Console.WriteLine(x.GetType())          ' Prints System.Int32
Console.WriteLine(GetType(Integer))   ' Prints System.Int32
Console.WriteLine(TypeName(x))        ' Prints Integer

Type Conversion
Dim d As Single = 3.5
Dim i As Integer = CType(d, Integer)   ' set to 4 (Banker's rounding)
i = CInt(d)  ' same result as CType
i = Int(d)    ' set to 3 (Int function truncates the decimal)

Value Types
bool
byte, sbyte
char
short, ushort, int, uint, long, ulong
float, double
decimal
DateTime   (not a built-in C# type)

Reference Types
object
string

Initializing
bool correct = true;
byte b = 0x2A;   // hex
object person = null;
string name = "Dwight";
char grade = 'B';
DateTime today = DateTime.Parse("12/31/2007 12:15:00");
decimal amount = 35.99m;
float gpa = 2.9f;
double pi = 3.14159265;
long lTotal = 123456L;
short sTotal = 123;
ushort usTotal = 123;
uint uiTotal = 123;
ulong ulTotal = 123;

Type Information
int x;
Console.WriteLine(x.GetType());              // Prints System.Int32
Console.WriteLine(typeof(int));               // Prints System.Int32
Console.WriteLine(x.GetType().Name);   // prints Int32

Type Conversion
float d = 3.5f;
int i = (int)d;   // set to 3  (truncates decimal)

VB.NET

Constants

C#

Const MAX_STUDENTS As Integer = 25

' Can set to a const or var; may be initialized in a constructor
ReadOnly MIN_DIAMETER As Single = 4.93

const int MAX_STUDENTS = 25;

// Can set to a const or var; may be initialized in a constructor
readonly float MIN_DIAMETER = 4.93f;

VB.NET

Enumerations

C#

Enum Action
  Start 
  [Stop]   ' Stop is a reserved word
  Rewind
  Forward
End Enum
Enum Status
  Flunk = 50
  Pass = 70
  Excel = 90
End Enum

Dim a As Action = Action.Stop
If a <> Action.Start Then _
   Console.WriteLine(a.ToString & " is " & a)     ' Prints "Stop is 1"
Console.WriteLine(Status.Pass)     ' Prints 70
Console.WriteLine(Status.Pass.ToString())     ' Prints Pass

enum Action {Start, Stop, Rewind, Forward};
enum Status {Flunk = 50, Pass = 70, Excel = 90};
Action a = Action.Stop;
if (a != Action.Start)
  Console.WriteLine(a + " is " + (int) a);    // Prints "Stop is 1"
Console.WriteLine((int) Status.Pass);    // Prints 70
Console.WriteLine(Status.Pass);      // Prints Pass

VB.NET

Operators

C#

Comparison
=  <  >  <=  >=  <>

Arithmetic
+  -  *  /
Mod
\  (integer division)
^  (raise to a power)

Assignment
=  +=  -=  *=  /=  \=  ^=  <<=  >>=  &=

Bitwise
And   Or   Xor   Not   <<   >>

Logical
AndAlso   OrElse   And   Or   Xor   Not

Note: AndAlso and OrElse perform short-circuit logical evaluations

String Concatenation
&

Comparison
==  <  >  <=  >=  !=

Arithmetic
+  -  *  /
%  (mod)
/  (integer division if both operands are ints)
Math.Pow(x, y)

Assignment
=  +=  -=  *=  /=   %=  &=  |=  ^=  <<=  >>=  ++  --

Bitwise
&   |   ^   ~   <<   >>

Logical
&&   ||   &   |   ^   !

Note: && and || perform short-circuit logical evaluations

String Concatenation
+

VB.NET

Choices

C#

' Ternary/Conditional operator (Iff evaluates 2nd and 3rd expressions)
greeting = If(age < 20, "What's up?", "Hello")

' One line doesn't require "End If"
If age < 20 Then greeting = "What's up?"
If age < 20 Then greeting = "What's up?" Else greeting = "Hello"

' Use : to put two commands on same line
If x <> 100 AndAlso y < 5 Then x *= 5 : y *= 2 

' Preferred
If x <> 100 AndAlso y < 5 Then
  x *= 5
  y *= 2
End If

' To break up any long single line use _
If whenYouHaveAReally < longLine And _
  itNeedsToBeBrokenInto2 > Lines Then _
  UseTheUnderscore(charToBreakItUp)

'If x > 5 Then
  x *= y
ElseIf x = 5 OrElse y Mod 2 = 0 Then
  x += y
ElseIf x < 10 Then
  x -= y
Else
  x /= y
End If

Select Case color   ' Must be a primitive data type
Case "pink", "red"
    r += 1
Case "blue"
    b += 1
Case "green"
    g += 1
Case Else
    other += 1
End Select

// Ternary/Conditional operator
greeting = age < 20 ? "What's up?" : "Hello";

if (age < 20)
  greeting = "What's up?";
else
  greeting = "Hello";

// Multiple statements must be enclosed in {}
if (x != 100 && y < 5) {   
  x *= 5;
  y *= 2;
}

No need for _ or : since ; is used to terminate each statement.


if (x > 5)
  x *= y;
else if (x == 5 || y % 2 == 0)
  x += y;
else if (x < 10)
  x -= y;
else
  x /= y;

// Every case must end with break or goto case
switch (color) {                          // Must be integer or string
case "pink":
case "red":    r++;    break;
case "blue":   b++;   break;
case "green": g++;   break;
default:    other++;  break; // break necessary on default
}

VB.NET

Loops

C#

Pre-test Loops:

While c < 10
  c += 1
End While

Do Until c = 10 
  c += 1
Loop

Do While c < 10
  c += 1
Loop

For c = 2 To 10 Step 2
  Console.WriteLine(c)
Next


Post-test Loops:

Do
  c += 1
Loop While c < 10

Do
  c += 1
Loop Until c = 10

'  Array or collection looping
Dim names As String() = {"Fred", "Sue", "Barney"}
For Each s As String In names
  Console.WriteLine(s)
Next

' Breaking out of loops
Dim i As Integer = 0
While (True)
  If (i = 5) Then Exit While
  i += 1
End While

' Continue to next iteration
For i = 0 To 4
  If i < 4 Then Continue For
  Console.WriteLine(i)   ' Only prints 4
Next

Pre-test Loops:

// no "until" keyword
while (c < 10)
  c++;
for (c = 2; c <= 10; c += 2)
  Console.WriteLine(c);

Post-test Loop:
do
  c++;
while (c < 10);

// Array or collection looping
string[] names = {"Fred", "Sue", "Barney"};
foreach (string s in names)
  Console.WriteLine(s);

// Breaking out of loops
int i = 0;
while (true) {
  if (i == 5)
break;
  i++;
}

// Continue to next iteration
for (i = 0; i < 5; i++) {
  if (i < 4)
continue;
  Console.WriteLine(i);   // Only prints 4
}

VB.NET

Arrays

C#

Dim nums() As Integer = {1, 2, 3} 
For i As Integer = 0 To nums.Length - 1
  Console.WriteLine(nums(i))
Next
' 4 is the index of the last element, so it holds 5 elements
Dim names(4) As String
names(0) = "David"
names(5) = "Bobby"  ' Throws System.IndexOutOfRangeException
' Resize the array, keeping the existing values (Preserve is optional)
ReDim Preserve names(6)

Dim twoD(rows-1, cols-1) As Single
twoD(2, 0) = 4.5
Dim jagged()() As Integer = { _
  New Integer(4) {}, New Integer(1) {}, New Integer(2) {} }
jagged(0)(4) = 5

int[] nums = {1, 2, 3};
for (int i = 0; i < nums.Length; i++)
  Console.WriteLine(nums[i]);
// 5 is the size of the array
string[] names = new string[5];
names[0] = "David";
names[5] = "Bobby";   // Throws System.IndexOutOfRangeException
// C# can't dynamically resize an array.  Just copy into new array.
string[] names2 = new string[7];
Array.Copy(names, names2, names.Length);   // or names.CopyTo(names2, 0);

float[,] twoD = new float[rows, cols];
twoD[2,0] = 4.5f;

int[][] jagged = new int[3][] {
  new int[5], new int[2], new int[3] };
jagged[0][4] = 5;

VB.NET

Functions

C#

' Pass by value (in, default), reference (in/out), and reference (out)
Sub TestFunc(ByVal x As Integer, ByRef y As Integer, ByRefz As Integer)
  x += 1
  y += 1
  z = 5
End Sub

Dim a = 1, b = 1, c As Integer   ' c set to zero by default
TestFunc(a, b, c)
Console.WriteLine("{0} {1} {2}", a, b, c)   ' 1 2 5

' Accept variable number of arguments
Function Sum(ByVal ParamArray nums As Integer()) As Integer
  Sum = 0 
  For Each i As Integer In nums
    Sum += i
  Next
End Function ' Or use Return statement like C#
Dim total As Integer = Sum(4, 3, 2, 1)   ' returns 10

' Optional parameters must be listed last and must have a default value
Sub SayHello(ByVal name As String, Optional ByVal prefix As String = "")
  Console.WriteLine("Greetings, " & prefix & " " & name)
End Sub
SayHello("Strangelove", "Dr.")
SayHello("Madonna")

// Pass by value (in, default), reference (in/out), and reference (out)
void TestFunc(int x, ref int y, out int z) {
  x++;  
  y++;
  z = 5;
}

int a = 1, b = 1, c;  // c doesn't need initializing
TestFunc(a, ref b, out c);
Console.WriteLine("{0} {1} {2}", a, b, c);  // 1 2 5

// Accept variable number of arguments
int Sum(params int[] nums) {
  int sum = 0;
  foreach (int i in nums)
    sum += i;
  return sum;
}

int total = Sum(4, 3, 2, 1);   // returns 10

/* C# doesn't support optional arguments/parameters.  Just create two different versions of the same function. */
void SayHello(string name, string prefix) {
  Console.WriteLine("Greetings, " + prefix + " " + name);
} 
void SayHello(string name) {
  SayHello(name, "");
}

VB.NET

Strings

C#

Special character constants (all also accessible from ControlChars class)
vbCrLf, vbCr, vbLf, vbNewLine
vbNullString
vbTab
vbBack
vbFormFeed
vbVerticalTab
""

' String concatenation (use & or +)
Dim school As String = "Harding" & vbTab
school = school & "University" ' school is "Harding (tab) University"

' Chars
Dim letter As Char = school.Chars(0)   ' letter is H
letter = Convert.ToChar(65)                ' letter is A
letter = Chr(65)                                 ' same thing
Dim word() As Char = school.ToCharArray() ' word holds Harding

' No string literal operator
Dim msg As String = "File is c:\temp\x.dat"

' String comparison
Dim mascot As String = "Bisons"
If (mascot = "Bisons") Then   ' true
If (mascot.Equals("Bisons")) Then   ' true
If (mascot.ToUpper().Equals("BISONS")) Then  ' true
If (mascot.CompareTo("Bisons") = 0) Then   ' true

' String matching with Like - Regex is more powerful
If ("John 3:16" Like "Jo[Hh]? #:*") Then   'true

' Substring
s = mascot.Substring(2, 3)) ' s is "son"

' Replacement
s = mascot.Replace("sons", "nomial")) ' s is "Binomial"

' Split
Dim names As String = "Frank,Becky,Ethan,Braden"
Dim parts() As String = names.Split(",".ToCharArray())   ' One name in each slot

' Date to string
Dim dt As New DateTime(1973, 10, 12)
Dim s As String = "My birthday: " & dt.ToString("MMM dd, yyyy")   ' Oct 12, 1973

' Integer to String
Dim x As Integer = 2
Dim y As String = x.ToString()     ' y is "2"

' String to Integer
Dim x As Integer = Convert.ToInt32("-5")     ' x is -5

' Mutable string
Dim buffer As New System.Text.StringBuilder("two ")
buffer.Append("three ")
buffer.Insert(0, "one ")
buffer.Replace("two", "TWO")
Console.WriteLine(buffer)         ' Prints "one TWO three"

Escape sequences
\r    // carriage-return
\n    // line-feed
\t    // tab
\\    // backslash
\"    // quote

// String concatenation
string school = "Harding\t";
school = school + "University";   // school is "Harding (tab) University"

// Chars
char letter = school[0];            // letter is H
letter = Convert.ToChar(65);     // letter is A
letter = (char)65;                    // same thing
char[] word = school.ToCharArray();   // word holds Harding

// String literal
string msg = @"File is c:\temp\x.dat";
// same as
string msg = "File is c:\\temp\\x.dat";

// String comparison
string mascot = "Bisons";
if (mascot == "Bisons")    // true
if (mascot.Equals("Bisons"))   // true
if (mascot.ToUpper().Equals("BISONS"))   // true
if (mascot.CompareTo("Bisons") == 0)    // true

// String matching - No Like equivalent, use Regex

// Substring
s = mascot.Substring(2, 3))     // s is "son"

// Replacement
s = mascot.Replace("sons", "nomial"))     // s is "Binomial"

// Split
string names = "Frank,Becky,Ethan,Braden";
string[] parts = names.Split(",".ToCharArray());   // One name in each slot

// Date to string
DateTime dt = new DateTime(1973, 10, 12);
string s = dt.ToString("MMM dd, yyyy");     // Oct 12, 1973

// int to string
int x = 2;
string y = x.ToString();     // y is "2"

// string to int
int x = Convert.ToInt32("-5");     // x is -5

// Mutable string
System.Text.StringBuilder buffer = new System.Text.StringBuilder("two ");
buffer.Append("three ");
buffer.Insert(0, "one ");
buffer.Replace("two", "TWO");
Console.WriteLine(buffer);     // Prints "one TWO three"

VB.NET

Regular Expressions

C#

Imports System.Text.RegularExpressions

' Match a string pattern
Dim r As New Regex("j[aeiou]h?. \d:*", RegexOptions.IgnoreCase Or _
        RegexOptions.Compiled)
If (r.Match("John 3:16").Success) Then   'true
    Console.WriteLine("Match")
End If

' Find and remember all matching patterns
Dim s As String = "My number is 305-1881, not 305-1818."
Dim r As New Regex("(\d+-\d+)")
Dim m As Match = r.Match(s)     ' Matches 305-1881 and 305-1818
While m.Success
    Console.WriteLine("Found number: " & m.Groups(1).Value & " at position " _
            & m.Groups(1).Index.ToString)
    m = m.NextMatch()
End While

' Remeber multiple parts of matched pattern
Dim r As New Regex("(\d\d):(\d\d) (am|pm)")
Dim m As Match = r.Match("We left at 03:15 pm.")
If m.Success Then
    Console.WriteLine("Hour: " & m.Groups(1).ToString)       ' 03
    Console.WriteLine("Min: " & m.Groups(2).ToString)         ' 15
    Console.WriteLine("Ending: " & m.Groups(3).ToString)   ' pm
End If

' Replace all occurrances of a pattern
Dim r As New Regex("h\w+?d", RegexOptions.IgnoreCase)
Dim s As String = r.Replace("I heard this was HARD!", "easy")  ' I easy this was easy!

' Replace matched patterns
Dim s As String = Regex.Replace("123 < 456", "(\d+) . (\d+)", "$2 > $1")   ' 456 > 123

' Split a string based on a pattern
Dim names As String = "Frank, Becky, Ethan, Braden"
Dim r As New Regex(",\s*")
Dim parts() As String = r.Split(names)   ' One name in each slot

using System.Text.RegularExpressions;

// Match a string pattern
Regex r = new Regex(@"j[aeiou]h?. \d:*", RegexOptions.IgnoreCase |
        RegexOptions.Compiled);
if (r.Match("John 3:16").Success)   // true
    Console.WriteLine("Match");

// Find and remember all matching patterns
string s = "My number is 305-1881, not 305-1818.";
Regex r = new Regex("(\\d+-\\d+)");
// Matches 305-1881 and 305-1818
for (Match m = r.Match(s); m.Success; m = m.NextMatch())
    Console.WriteLine("Found number: " + m.Groups[1] + " at position " +
        m.Groups[1].Index);

// Remeber multiple parts of matched pattern
Regex r = new Regex("@(\d\d):(\d\d) (am|pm)");
Match m = r.Match("We left at 03:15 pm.");
if (m.Success) {
    Console.WriteLine("Hour: " + m.Groups[1]);       // 03
    Console.WriteLine("Min: " + m.Groups[2]);         // 15
    Console.WriteLine("Ending: " + m.Groups[3]);   // pm
}

// Replace all occurrances of a pattern
Regex r = new Regex("h\\w+?d", RegexOptions.IgnoreCase);
string s = r.Replace("I heard this was HARD!", "easy"));   // I easy this was easy!

// Replace matched patterns
string s = Regex.Replace("123 < 456", @"(\d+) . (\d+)", "$2 > $1");   // 456 > 123

// Split a string based on a pattern
string names = "Frank, Becky, Ethan, Braden";
Regex r = new Regex(@",\s*");
string[] parts = r.Split(names);   // One name in each slot

VB.NET

Exception Handling

C#

' Throw an exception
Dim ex As New Exception("Something is really wrong.")
Throw  ex

' Catch an exception
Try
  y = 0
  x = 10 / y
Catch ex As Exception When y = 0 ' Argument and When is optional
  Console.WriteLine(ex.Message)
Finally
  Beep()
End Try

' Deprecated unstructured error handling
On Error GoTo MyErrorHandler
...
MyErrorHandler: Console.WriteLine(Err.Description)

// Throw an exception
Exception up = new Exception("Something is really wrong.");
throw up;  // ha ha

// Catch an exception
try { 
  y = 0;
  x = 10 / y;
}
catch (Exception ex) {   // Argument is optional, no "When" keyword
  Console.WriteLine(ex.Message);
}
finally {
  Microsoft.VisualBasic.Interaction.Beep();
}

VB.NET

Namespaces

C#

Namespace Harding.Compsci.Graphics 
  ...
End Namespace

' or

Namespace Harding
Namespace Compsci
Namespace Graphics 
      ...
End Namespace
End Namespace
End Namespace

Imports Harding.Compsci.Graphics

namespace Harding.Compsci.Graphics {
  ...
}

// or

namespace Harding {
namespace Compsci {
namespace Graphics {
      ...
    }
  }
}

using Harding.Compsci.Graphics;

VB.NET

Classes / Interfaces

C#

Accessibility keywords
Public
Private
Friend                   
Protected
Protected Friend
Shared

' Inheritance
Class FootballGame
Inherits Competition
  ...
End Class

' Interface definition
Interface IAlarmClock 
  ...
End Interface

// Extending an interface
Interface IAlarmClock
Inherits IClock
  ...
End Interface

// Interface implementation
Class WristWatch 
Implements IAlarmClock, ITimer 
   ...
End Class

Accessibility keywords
public
private
internal
protected
protected internal
static

// Inheritance
class FootballGame : Competition {
  ...
}


// Interface definition
interface IAlarmClock {
  ...
}

// Extending an interface
interface IAlarmClock : IClock {
  ...
}


// Interface implementation
class WristWatch : IAlarmClock, ITimer {
   ...
}

VB.NET

Constructors / Destructors

C#

Class SuperHero
  Private _powerLevel As Integer
  Public Sub New()
    _powerLevel = 0
  End Sub
  Public Sub New(ByVal powerLevel As Integer)
    Me._powerLevel = powerLevel
  End Sub
  Protected Overrides Sub Finalize() 
' Desctructor code to free unmanaged resources
    MyBase.Finalize()
  End Sub
End Class

class SuperHero {
  private int _powerLevel;
  public SuperHero() {
     _powerLevel = 0;
  }
  public SuperHero(int powerLevel) {
    this._powerLevel= powerLevel; 
  }
~SuperHero() {
// Destructor code to free unmanaged resources.
    // Implicitly creates a Finalize method
  }
}

VB.NET

Using Objects

C#

Dim hero As SuperHero = New SuperHero
' or
Dim hero As New SuperHero

With hero
  .Name = "SpamMan"
  .PowerLevel = 3
End With

hero.Defend("Laura Jones")
hero.Rest()     ' Calling Shared method
' or
SuperHero.Rest()

Dim hero2 As SuperHero = hero  ' Both reference the same object
hero2.Name = "WormWoman"
Console.WriteLine(hero.Name)   ' Prints WormWoman

hero = Nothing ' Free the object

If hero Is Nothing Then _
  hero = New SuperHero

Dim obj As Object = New SuperHero
If TypeOf obj Is SuperHero Then _
  Console.WriteLine("Is a SuperHero object.")

' Mark object for quick disposal
Using reader As StreamReader = File.OpenText("test.txt")
  Dim line As String = reader.ReadLine()
  While Not line Is Nothing
    Console.WriteLine(line)
    line = reader.ReadLine()
  End While
End Using

SuperHero hero = new SuperHero();

// No "With" construct
hero.Name = "SpamMan";
hero.PowerLevel = 3;

hero.Defend("Laura Jones");
SuperHero.Rest();   // Calling static method

SuperHero hero2 = hero;   // Both reference the same object
hero2.Name = "WormWoman";
Console.WriteLine(hero.Name);   // Prints WormWoman

hero = null ;   // Free the object

if (hero == null)
  hero = new SuperHero();

Object obj = new SuperHero(); 
if (obj is SuperHero)
  Console.WriteLine("Is a SuperHero object.");

// Mark object for quick disposal
using (StreamReader reader = File.OpenText("test.txt")) {
  string line;
  while ((line = reader.ReadLine()) != null)
    Console.WriteLine(line);
}

VB.NET

Structs

C#

Structure StudentRecord
  Public name As String
  Public gpa As Single
  Public Sub New(ByVal name As String, ByVal gpa As Single)
    Me.name = name
    Me.gpa = gpa
  End Sub
End Structure

Dim stu As StudentRecord = New StudentRecord("Bob", 3.5)
Dim stu2 As StudentRecord = stu  
stu2.name = "Sue"
Console.WriteLine(stu.name)    ' Prints Bob
Console.WriteLine(stu2.name)  ' Prints Sue

struct StudentRecord {
  public string name;
  public float gpa;
  public StudentRecord(string name, float gpa) {
    this.name = name;
    this.gpa = gpa;
  }
}

StudentRecord stu = new StudentRecord("Bob", 3.5f);
StudentRecord stu2 = stu;  
stu2.name = "Sue";
Console.WriteLine(stu.name);    // Prints Bob
Console.WriteLine(stu2.name);   // Prints Sue

VB.NET

Properties

C#

Private _size As Integer
Public Property Size() As Integer
Get
    Return _size
End Get
Set (ByVal Value As Integer)
    If Value < 0 Then
      _size = 0
    Else
      _size = Value
    End If
End Set
End Property

foo.Size += 1

private int _size;
public int Size {
get {
    return _size;
  }
set {
    if (value < 0)
      _size = 0;
    else
      _size = value;
  }
}

foo.Size++;

VB.NET

Delegates / Events

C#

Delegate Sub MsgArrivedEventHandler(ByVal message As String)

Event MsgArrivedEvent As MsgArrivedEventHandler

' or to define an event which declares a delegate implicitly
Event MsgArrivedEvent(ByVal message As String)

AddHandler MsgArrivedEvent, AddressOfMy_MsgArrivedCallback
' Won't throw an exception if obj is Nothing
RaiseEvent MsgArrivedEvent("Test message")
RemoveHandler MsgArrivedEvent, AddressOfMy_MsgArrivedCallback

Imports System.Windows.Forms

Dim WithEvents MyButton As Button   ' WithEvents can't be used on local variable
MyButton = New Button

Private Sub MyButton_Click(ByVal sender As System.Object, _
  ByVal e As System.EventArgs) Handles MyButton.Click
  MessageBox.Show(Me, "Button was clicked", "Info", _
    MessageBoxButtons.OK, MessageBoxIcon.Information)
End Sub

delegate void MsgArrivedEventHandler(string message);

event MsgArrivedEventHandler MsgArrivedEvent;

// Delegates must be used with events in C#
MsgArrivedEvent += new MsgArrivedEventHandler(My_MsgArrivedEventCallback);
MsgArrivedEvent("Test message");    // Throws exception if obj is null
MsgArrivedEvent -= new MsgArrivedEventHandler(My_MsgArrivedEventCallback);

using System.Windows.Forms;

Button MyButton = new Button(); 
MyButton.Click += new System.EventHandler(MyButton_Click);

private void MyButton_Click(object sender, System.EventArgs e) {
  MessageBox.Show(this, "Button was clicked", "Info",
    MessageBoxButtons.OK, MessageBoxIcon.Information);
}

VB.NET

Console I/O

C#

Console.Write("What's your name? ")
Dim name As String = Console.ReadLine()
Console.Write("How old are you? ")
Dim age As Integer = Val(Console.ReadLine())
Console.WriteLine("{0} is {1} years old.", name, age) 
' or
Console.WriteLine(name & " is " & age & " years old.")
Dim c As Integer
c = Console.Read()    ' Read single char
Console.WriteLine(c)   ' Prints 65 if user enters "A"

Console.Write("What's your name? ");
string name = Console.ReadLine();
Console.Write("How old are you? ");
int age = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("{0} is {1} years old.", name, age);
// or
Console.WriteLine(name + " is " + age + " years old.");

int c = Console.Read();  // Read single char
Console.WriteLine(c);    // Prints 65 if user enters "A"

VB.NET

File I/O

C#

Imports System.IO

' Write out to text file
Dim writer As StreamWriter = File.CreateText("c:\myfile.txt")
writer.WriteLine("Out to file.")
writer.Close()

' Read all lines from text file
Dim reader As StreamReader = File.OpenText("c:\myfile.txt")
Dim line As String = reader.ReadLine()
While Not line Is Nothing
  Console.WriteLine(line)
  line = reader.ReadLine()
End While
reader.Close()

' Write out to binary file
Dim str As String = "Text data"
Dim num As Integer = 123
Dim binWriter As NewBinaryWriter(File.OpenWrite("c:\myfile.dat")) 
binWriter.Write(str) 
binWriter.Write(num) 
binWriter.Close()

' Read from binary file
Dim binReader As NewBinaryReader(File.OpenRead("c:\myfile.dat"))
str = binReader.ReadString()
num = binReader.ReadInt32()
binReader.Close()

using System.IO;

// Write out to text file
StreamWriter writer = File.CreateText("c:\\myfile.txt");
writer.WriteLine("Out to file.");
writer.Close();

// Read all lines from text file
StreamReader reader = File.OpenText("c:\\myfile.txt");
string line = reader.ReadLine();
while (line != null) {
  Console.WriteLine(line);
  line = reader.ReadLine();
}
reader.Close();

// Write out to binary file
string str = "Text data";
int num = 123;
BinaryWriter binWriter = new BinaryWriter(File.OpenWrite("c:\\myfile.dat"));
binWriter.Write(str);
binWriter.Write(num);
binWriter.Close();

// Read from binary file
BinaryReader binReader = new BinaryReader(File.OpenRead("c:\\myfile.dat"));
str = binReader.ReadString();
num = binReader.ReadInt32();
binReader.Close();

VB.NET, C#, Programming , ,

Sending Generic.List collection back to WCF ObservableCollection

16. December 2009
Comments (2)

Found a good article and helped with a problem I was having, trying to send a list of collection back to a WCF service that was set to accept Observable Collections. 

Source: http://smehrozalam.wordpress.com/2009/01/18/ienumerabletoobservablecollection/

In WPF/Silverlight, binding UI objects such as DataGrid or ListBox to collections is typically done using an ObservableCollectioninstead of the generic List object. This way, our UI is automatically synchronized since the observable collection provides event notification to WPF data binding engine whenever items are added, removed, or when the whole list is refreshed. The LINQ extension methods that return a collection actually return IEnumerable<T>. The .NET framework for Silverlight provides built-in extension methods to convert IEnumerable<T> to List<T> and Array<T> but there’s no method available to convert the collection to ObservableCollection<T>(WPF developers can simply use this constructor overload) . So here’s one you may find useful:

  1. Public Static Class CollectionExtensions
  2. {
  3.     public static ObservableCollection<T> ToObservableCollection<T>(this IEnumerable<T> enumerableList)
  4.     {
  5.         if (enumerableList != null)
  6.         {
  7.             //create an emtpy observable collection object
  8.             var observableCollection = new ObservableCollection<T>();
  9.  
  10.             //loop through all the records and add to observable collection object
  11.             foreach (var item in enumerableList)
  12.                 observableCollection.Add(item);
  13.  
  14.             //return the populated observable collection
  15.             return observableCollection;
  16.         }
  17.         return null;
  18.     }
  19. }

Extension methods are very powerful and I am planning to post an example demonstrating their potential.

I’ve converted the above example to VB.Net version for you to copy.

Public Shared Function ToObservableCollection(Of T)(ByVal enumerableList As IEnumerable(Of T)) As ObservableCollection(Of T)
    If enumerableList IsNot Nothing Then
        'create an emtpy observable collection object
        Dim observableCollection As New ObservableCollection(Of T)()

        'loop through all the records and add to observable collection object
        For Each item As T In enumerableList
            observableCollection.Add(item)
        Next

        'return the populated observable collection
        Return observableCollection
    End If
    Return Nothing
End Function

Now you can call your List and send it back as a ObservableCollection

.Net Framework, Code Snippets, Programming, VB.NET, WCF, SilverLight , , , ,

Mapping a DataTable to an Object Class. Like a homemade Linq to SQL. Send over WCF to SilverLight

8. December 2009
Comments (0)

Application Foundation

An application I work has architecture in a way where we have a Class object that represents each table. So for example we might have a “Customer” table in the database. So our class would be something like..

Customer.vb class file…

Public Class Customer

    Private _FirstName As String = String.Empty
    Public Property FirstName() As String
        Get
            Return _FirstName
        End Get
        Set(ByVal value As String)
            _FirstName = value
        End Set
    End Property

    Private _LastName As String = String.Empty
    Public Property LastName() As String
        Get
            Return _LastName
        End Get
        Set(ByVal value As String)
            _LastName = value
        End Set
    End Property

End Class

In this class is a function to say list all customers, we call this “GetList” method. You might use another way to bring back a list of data. Ideally now we’d want to bring back Enumerable Lists, but the app was already structured for DataSets and DataTables. So I was trying to reuse what we had.

Customer.vb class file

Public Function GetList() As Data.DataTable
    Dim oDS As Data.DataSet
    Try
        oDS = DataAccess.SqlHelper.ExecuteDataset(_ConnectionString, Data.CommandType.StoredProcedure, "CustomerGetList")
        Return oDS.Tables(0)
    Catch ex As Exception
        Throw ex
    Finally
        oDS = Nothing
    End Try
End Function

So on our pages we might do something like this…

Default.aspx.vb

Protected Sub Button1_ClickSave()
    Dim oCustomer As New Customer
    oCustomer.FirstName = "Fred"
    oCustomer.LastName = "Mastro"
    oCustomer.SaveToDB()

    GridView1.DataSource = oCustomer.GetList()
    GridView1.DataBind()

    oCustomer = Nothing

End Sub

 

And this returns a nice DataTable and populates the grid. Great!

Problem Areas over WCF to SliverLight

I was working on a SilverLight application that would talk to an existing business application, to pull back and list records.  I had to use a Service, so I went with WCF since RIA.Net is not in production yet.  The problem was that DataTables can not be serialized and set over WCF to SilverLight.  So I tried messing with Linq to SQL to pull data back and populate classes I already had, but LinqTables are not serializable either, and instead of modifying all the Linq classes generated in my class I wanted to find an easier solution.

DataTable to List(Of Customer) Solution

I can across these two posts: Datatable to List of Objects Mapper and Creating datarow to object mapper and was amazed. Using reflection Chris Rock (lol) was able to read the properties of the object and map each column of the datatable to the desired property of the object. This is what I’m looking to do.  This would manually mimic Linq type functionality. The Bulk of the code is this

My Helper.vb class file

  1.  
  2. Public Class Helper
  3.  
  4.     Public Function MapDatarowToObject(Of T)(ByVal dr As DataRow) As T
  5.         Try
  6.  
  7.             If dr Is Nothing Then
  8.                 Return Nothing
  9.             End If
  10.  
  11.             Dim instance As T = Activator.CreateInstance(Of T)()
  12.  
  13.             Dim properties() As Reflection.PropertyInfo = instance.GetType().GetProperties()
  14.  
  15.             If (properties.Length > 0) Then
  16.                 For Each propertyObject As Reflection.PropertyInfo In properties
  17.  
  18.                     Dim valueSet As Boolean = False
  19.  
  20.                     For Each attributeObject As Object In propertyObject.GetCustomAttributes(False)
  21.  
  22.                         If attributeObject.GetType() Is GetType(MapperColumn) Then
  23.                             Dim columnAttributeObject As MapperColumn = CType(attributeObject, MapperColumn)
  24.  
  25.                             If (columnAttributeObject.ColumnName <> String.Empty) Then
  26.  
  27.                                 If dr.Table.Columns.Contains(columnAttributeObject.ColumnName) AndAlso Not dr(columnAttributeObject.ColumnName) Is DBNull.Value Then
  28.                                     propertyObject.SetValue(instance, dr(columnAttributeObject.ColumnName), Nothing)
  29.                                     valueSet = True
  30.  
  31.                                 End If
  32.  
  33.                             End If
  34.                         End If
  35.                     Next
  36.  
  37.                     If Not valueSet Then
  38.                         If dr.Table.Columns.Contains(propertyObject.Name) AndAlso Not dr(propertyObject.Name) Is DBNull.Value Then
  39.                             propertyObject.SetValue(instance, dr(propertyObject.Name), Nothing)
  40.                         End If
  41.                     End If
  42.  
  43.                 Next
  44.             End If
  45.  
  46.             Return instance
  47.         Catch ex As Exception
  48.             Throw ex
  49.         End Try
  50.     End Function
  51.  
  52.     Public Function MapDataTableToList(Of T)(ByVal dt As DataTable) As Collections.Generic.IList(Of T)
  53.         If dt Is Nothing Then
  54.             Return Nothing
  55.         End If
  56.  
  57.         Dim list As IList(Of T) = New List(Of T)
  58.  
  59.         For Each dr As DataRow In dt.Rows
  60.             list.Add(MapDatarowToObject(Of T)(dr))
  61.         Next
  62.  
  63.         Return list
  64.     End Function
  65.  
  66. End Class
  67.  
  68. <AttributeUsage(AttributeTargets.Property)> _
  69. Public Class MapperColumn
  70.     Inherits Attribute
  71.  
  72.     Private mColumnName As String
  73.  
  74.     Public Sub New(ByVal columnName As String)
  75.         mColumnName = columnName
  76.     End Sub
  77.  
  78.     Public Property ColumnName() As String
  79.         Get
  80.             Return mColumnName
  81.         End Get
  82.         Set(ByVal value As String)
  83.             mColumnName = value
  84.         End Set
  85.     End Property
  86.  
  87. End Class

Using Mapper in WCF

Now in my WCF Service methods I can just instantiate Customers like I always do in the normal application and apply the new Mapper method to get a List of the class objects.

WCFServiceMethods.vb file (which is code-behind to WCFServiceMethods.svc)

  1. Imports System.ServiceModel
  2. Imports System.ServiceModel.Activation
  3. Imports System.Runtime.Serialization 'For DataContract
  4. Imports System.Collections.Generic
  5.  
  6. <ServiceContract(Namespace:="")> _
  7. <ServiceBehavior(IncludeExceptionDetailInFaults:=True)> _
  8. <AspNetCompatibilityRequirements(RequirementsMode:=AspNetCompatibilityRequirementsMode.Allowed)> _
  9. Public Class WCFServiceMethods
  10.     <OperationContract()> _
  11.     Public Function GetCustomers() As Collections.Generic.List(Of Customer)
  12.         Dim oCustomer As New Customer
  13.  
  14.         Dim Customers As Collections.Generic.List(Of Customer)
  15.         Customers = Helper.MapDataTableToList(Of Customer)(oCustomer.GetList())
  16.  
  17.         oCustomer = Nothing
  18.         Return Customers
  19.  
  20.     End Function
  21. End Class

You’ll see in Line 15, I can take the DataTable and now create a List(Of Customer) object, which is serializable and send it over the wire.

Applying it in SilverLight or Other Application that uses your WCF Service

Assuming you referenced your WCF Service.. Now on my SilverLight app on a button click I can get the List of Customers and show it natively in a datagrid.

MainPage.xaml code-behind

Private Sub btnSearch_Click(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs) Handles btnSearch.Click
    Dim oWCFProxy As New WCFService.WCFServiceClient

    AddHandler oWCFProxy.GetCustomers, AddressOf oWCFProxy_GetCustomersCompleted
    oWCFProxy.GetCustomersAsync()

    oWCFProxy = Nothing

End Sub

Private Sub oWCFProxy_GetCustomersCompleted(ByVal sender As Object, ByVal e As WCFService.GetCustomersCompletedEventArgs)
    Dim Customers As Collections.ObjectModel.Collection(Of oWCFProxy.Customer)
    Customers = e.Result

    DataGrid1.ItemsSource = Customers
End Sub

Problem Area With Mapper Casting Types and Solution

So with all that above you should have enough to re-create all this. Read through Chris’ posts because it does a good job of explaining the mapper.  I ran into a problem with the mapper though on line 39. Problem is when it tries to map data from the database, it all comes back as a string, and you don’t know until run-time what System.Type you need, so you can’t CType or DirectCast by using System.Type.GetType(), so I had to create a crappy function to Throw ex check every possible combination. This the best way? I sure hope it isn’t. Hope to find a better solution for it but was pressed for time.

So what was my crappy solution? I don’t even want to post it haha. I swapped out line 39 and 28 with the a call to this method of 1531 lines of code.

Private Sub TryCastTypeToPropertyType(ByRef propertyObject As Reflection.PropertyInfo, ByRef instance As Object, ByRef dr As DataRow, ByRef ColumnName As String)

        Try
            'Try to Default Types
            propertyObject.SetValue(instance, dr(ColumnName), Nothing)
        Catch exDefault1 As InvalidCastException
            Try
                'Try to String
                propertyObject.SetValue(instance, CType(dr(ColumnName), String), Nothing)
            Catch exString1 As InvalidCastException
                'Try to Integer
                Try
                    propertyObject.SetValue(instance, CType(dr(ColumnName), Integer), Nothing)
                Catch exInt32a As ArgumentException
                    'Try to DateTime
                    Try
                        propertyObject.SetValue(instance, CType(dr(ColumnName), DateTime), Nothing)
                    Catch exDate1 As ArgumentException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    Catch exDate2 As InvalidCastException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    End Try
                Catch exInt32b As InvalidCastException
                    'Try to DateTime
                    Try
                        propertyObject.SetValue(instance, CType(dr(ColumnName), DateTime), Nothing)
                    Catch exDate1 As ArgumentException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    Catch exDate2 As InvalidCastException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    End Try
                End Try
            Catch exString2 As ArgumentException
                'Try to Integer
                Try
                    propertyObject.SetValue(instance, CType(dr(ColumnName), Integer), Nothing)
                Catch exInt32a As ArgumentException
                    'Try to DateTime
                    Try
                        propertyObject.SetValue(instance, CType(dr(ColumnName), DateTime), Nothing)
                    Catch exDate1 As ArgumentException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    Catch exDate2 As InvalidCastException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    End Try
                Catch exInt32b As InvalidCastException
                    'Try to DateTime
                    Try
                        propertyObject.SetValue(instance, CType(dr(ColumnName), DateTime), Nothing)
                    Catch exDate1 As ArgumentException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    Catch exDate2 As InvalidCastException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    End Try
                End Try
            End Try
        Catch exDefault2 As ArgumentException
            Try
                'Try to String
                propertyObject.SetValue(instance, CType(dr(ColumnName), String), Nothing)
            Catch exString1 As InvalidCastException
                'Try to Integer
                Try
                    propertyObject.SetValue(instance, CType(dr(ColumnName), Integer), Nothing)
                Catch exInt32a As ArgumentException
                    'Try to DateTime
                    Try
                        propertyObject.SetValue(instance, CType(dr(ColumnName), DateTime), Nothing)
                    Catch exDate1 As ArgumentException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    Catch exDate2 As InvalidCastException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    End Try
                Catch exInt32b As InvalidCastException
                    'Try to DateTime
                    Try
                        propertyObject.SetValue(instance, CType(dr(ColumnName), DateTime), Nothing)
                    Catch exDate1 As ArgumentException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    Catch exDate2 As InvalidCastException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    End Try
                End Try
            Catch exString2 As ArgumentException
                'Try to Integer
                Try
                    propertyObject.SetValue(instance, CType(dr(ColumnName), Integer), Nothing)
                Catch exInt32a As ArgumentException
                    'Try to DateTime
                    Try
                        propertyObject.SetValue(instance, CType(dr(ColumnName), DateTime), Nothing)
                    Catch exDate1 As ArgumentException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    Catch exDate2 As InvalidCastException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    End Try
                Catch exInt32b As InvalidCastException
                    'Try to DateTime
                    Try
                        propertyObject.SetValue(instance, CType(dr(ColumnName), DateTime), Nothing)
                    Catch exDate1 As ArgumentException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    Catch exDate2 As InvalidCastException
                        'Try to Decimal
                        Try
                            propertyObject.SetValue(instance, CType(dr(ColumnName), Decimal), Nothing)
                        Catch exDecimal1 As ArgumentException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        Catch exDecimal2 As InvalidCastException
                            'Try to Double
                            Try
                                propertyObject.SetValue(instance, CType(dr(ColumnName), Double), Nothing)
                            Catch exDouble1 As ArgumentException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            Catch exDouble2 As InvalidCastException
                                'Try to Boolean
                                Try
                                    propertyObject.SetValue(instance, CType(dr(ColumnName), Boolean), Nothing)
                                Catch exBoolean1 As ArgumentException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                Catch exBoolean2 As InvalidCastException
                                    'Try To Date
                                    Try
                                        propertyObject.SetValue(instance, CType(dr(ColumnName), Date), Nothing)
                                    Catch ex As Exception
                                        Throw ex
                                    End Try
                                End Try
                            End Try
                        End Try
                    End Try
                End Try
            End Try
        End Try
    End Sub

Maybe I’ll get lucky and someone will post up a “Oh you can just do this, which is new in .Net 3.5 or 4.0.. “ and I can get rid of this thing. But hey it works!

Resource: How to Consume WCF and ASP.Net Web Services in Silverlight

.Net Framework, Code Snippets, Programming, SilverLight, WCF, VB.NET , , ,

Convert Pipe Delimited File to CSV File and Choose and Reorder Columns

4. December 2009
Comments (0)

A friend need a small program to take a Pipe file and convert it to a CSV file. Easy enough, replace the “|”,s with “,”’s.  Until you add more requirements, allow the user to choose which columns they want to convert over and allow them to re-order the columns and save the file as something else.  Ok now you’re talking about streamreaders, streamwriter, some type or reorder control and choosing columns. Turning a 45min project into a  3 hour project going at full pace, as I’m not much of a Windows Form developer, I generally stick in the asp.net world.

Anyway.. here’s the project in VB.Net and source code.

The executable is in it’s default location TextPipeConverter\TextPipeConverter\bin\Debug\TextPipeConverter.exe

Notes: There’s no error checking, very minor, no try catches, quick and dirty.

VB.NET, Programming, Window Forms ,

Casting Types in VB.Net and More

2. December 2009
Comments (0)

Source: Cheat Sheet - Casting in VB.NET and C#

Great little find, and since I’m a VB.Net whore, I’ll just post up the VB.Net version :)

Casting in VB.NET

  1. By default in VB, casting is automatically done for you when you assign objects to variables. The objects are then automatically casted to the variables' type.

    This behavior can be influenced by an option line on top of your code file: 

    Option Strict On
    Option Strict Off

    When on, casting is strict and not automatic.

  2. Explicit casting can be done with the cast operator CType() or DirectCast(): 

    textbox = CType(obj, TextBox)
    textbox = DirectCast(obj, TextBox)


    The difference between the two keywords is that CType succeeds as long as there is a valid conversion defined between the expression and the type, whereas DirectCast requires the run-time type of an object variable to be the same as the specified type. If the specified type and the run-time type of the expression are the same, however, the run-time performance of DirectCast is better than that of CType. DirectCast throws an InvalidCastException error if the argument types do not match.

  3. Testing if an object is of a particular type, can be done with the TypeOf...Is operator: 

    If TypeOf obj Is TextBox Then...

  4. Obtaining a System.Type object for a given type can be done with the GetType operator: 

    Dim t As System.Type
    t = GetType(String)
    MessageBox.Show(t.FullName)

  5. Obtaining a System.Type object for a given object can be done with the GetType method: 

    Dim t as System.Type
    t = obj.GetType()
    MessageBox.Show(t.FullName)

Now to build on and add one more of my own…

Get the type based on an arbitrary string.

System.Type.GetType("System.String")

Problem with this though is you can not use it to cast using CType or DirectCast. Looking at the CType Function..

typename - Any expression that is legal within an As clause in a Dim statement, that is, the name of any data type, object, structure, class, or interface.

You can only use types that are compiled and can’t use types that show up at runtime. So trying to use CType(obj, System.Type.GetType(“System.String”)) will only get you an error.  Array bounds cannot appear in type specifiers.

How to get around this? I have no freaking idea, yet. I’m think I might could create a custom type of my own and do something so that it converts to the proper method but for now I’ll just catch a few ArgumentExceptions and try different cast types then.

Code Snippets, VB.NET, Programming, .Net Framework , , , ,

Set the DefaultButton inside a LoginView Control in a MasterPage

25. November 2009
Comments (0)

Ok if you google this you’ll get some solutions that say set the DefaultButton to ParentControlID$ButtonID

However, this didn’t work for me. I kept getting the same error no matter what I tried.

The DefaultButton of '<PanelID>' must be the ID of a control of type IButtonControl.

So I tried another approach that worked great.

On page load I found the Panel Control and found the button control and set the default button programmatically.

<asp:LoginView ID="LoginView1" runat="server">
    <AnonymousTemplate>
        <asp:Panel ID="pnlLogin" runat="server">
            <telerik:RadTextBox ID="tbUsername" runat="server" EmptyMessage="Username" />&nbsp;
            <telerik:RadTextBox ID="tbPassword" runat="server" EmptyMessage="Password" TextMode="Password" />&nbsp;
            <div id="SignIn" style="position: relative; z-index: 1; float: right; bottom: 21px;">
                 <asp:LinkButton ID="lbSignIn" runat="server" Font-Bold="true" Font-Size="Small" Text="SIGN IN" OnClick="lbSignIn_Click" />
            </div>
            <div id="divLoginLinks" style="position:relative; clear:both">
                <span class="GrayFooterFont"><asp:HyperLink ID="hlRegister" runat="server" Text="Register" NavigateUrl="~/Registration.aspx" /> | <asp:HyperLink ID="hlForgot" runat="server" Text="Forgot Password" NavigateUrl="~/ForgotPassword.aspx" /></span>
            </div>
        </asp:Panel>
    </AnonymousTemplate>
    <LoggedInTemplate>
        <small><asp:Label ID="lblLoggedInUsername" runat="server" /> | <asp:LinkButton ID="lbSignOut" runat="server" Text="SIGN OUT" OnClick="lbSignOut_Click" /></small>
        <asp:LinkButton ID="lbSignIn" runat="server" Font-Bold="true" Font-Size="Small" Text="SIGN IN" OnClick="lbSignIn_Click" CssClass="hidden" />
    </LoggedInTemplate>
</asp:LoginView>

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    'If User is not logged in do this        
    Dim pnlLogin As Panel
    Dim lbSignIn As LinkButton
    pnlLogin = CType(LoginView1.Controls(0).FindControl("pnlLogin"), Panel)
    lbSignIn = CType(LoginView1.Controls(0).FindControl("lbSignIn"), LinkButton)
    pnlLogin.DefaultButton = lbSignIn.ID
    pnlLogin = Nothing
    lbSignIn = Nothing
End Sub

I’m sure I could have just hardcoded the lblSignIn ID to the pnlLogin, but no idea why I didn’t.

ASP.NET, VB.NET, Code Snippets , ,

Quick Enum Snippet. Get Values or Names based on Name or Value

16. October 2009
Comments (0) 
Public Enum CCid
        A = 3
        D = 6
End Enum

'Get Name
Dim s As String = [Enum].GetName(GetType(CCid), 3)

'Get Value
Dim v As Integer = [Enum].Parse(GetType(CCid), "A")
However, I do it this way. Where I actually use the Enum Type and check to see if it exists first.
 

VB.NET, Code Snippets ,