Cross-thread operation not valid: Control accessed from a thread other than the thread it was created on (Multi-Threaded Applicaiton)

I was stuck on this for hours where the event raised from the class wouldn' t write to my textbox in the presentation layer.

I googled but could not find any concrete solution to this but at last after going through various websites i figured out the easier way to solve this.

This article will help users to call the function in the class and raise an event within the class and catch the event in form and display whatever message raised to the text boxes in multi threaded application (VB.net)

Lets go step by step now:

1. I have a form with command button cmdTest and text box txtAction where I display my messages raised from the class.

Private Sub cmdTest_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdTest.Click
Dim robot As New RobotProcess_Ama(Nothing)
AddHandler robot.TaskProcessed, AddressOf ActionLog
WorkerThread = New Threading.Thread(AddressOf robot.CheckQueue)
WorkerThread.Start()
End Sub

Private Sub ActionLog(ByVal FunctName As String, ByVal aMessage As String)
System.Windows.Forms.Control.CheckForIllegalCrossThreadCalls = False
txtAction.Text = TimeString & "From: " & FunctName & ":" & aMessage
System.Windows.Forms.Control.CheckForIllegalCrossThreadCalls = True
End Sub

Here i disabled checkforIllegalcrossThreadcalls and re-enabled them after finishing.

2. Now my class RobotProcess_Ama contains function called checkqueue and raises the message.

Public Sub CheckQueue()

Try
RaiseEvent TaskProcessed("From Class", TimeString & ": Creating log file")
' Threading.Thread.Sleep(200)

Catch ex As Exception
Throw ex
End Try
End Sub

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CakePHP: Auto populating foreign key dropdown fields

I wasted so much time figuring out to populate the drop down from foreign classes in cake PHP and wished it would be best if someone could have written from beginning to end to help the beginners of Cake like me.

Finally i figured it out and you guys can benefit from it.

I have two tables articles and users, user write articles so there is one to many relationship. I need user drop down in articles forms to say who is this user writing the article.

User table has
id
Name

Article table has
id
Title
user_id

So my Article Model will look like below:


My user model will look like below:


My Article Controller will look like below


The Add view will look like below:

Similarly Edit View will look like below

Hope this will help kick start your Cake Php learning ... enjoy coding

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OO database connection class in PHP

I got good OO database connectivity class for PHP tutorial in the following site:

http://blog.bluewebtechniques.com/2010/03/10/creating-a-php-oop-database-connection-class/comment-page-1/#comment-1081

Enjoy guys

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Blogger Tips And Tricks|Latest Tips For Bloggers: How To Add Google +1(plus) Button With Blogger Sha...

Blogger Tips And Tricks|Latest Tips For Bloggers: How To Add Google +1(plus) Button With Blogger Sha...: "This quick and easy tutorial will explain how to enable Google +1 Button with Blogger Share Buttons. If you are already using Blogger share ..."

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Disable close button in vb.net form without losing icon on the form

In a module write the following code:

'for close button declaration
Private Const MF_BYPOSITION = &H400
Private Const MF_REMOVE = &H1000
Private Const MF_DISABLED = &H2

Private Declare Function RemoveMenu Lib "user32" (ByVal hMenu As IntPtr, ByVal nPosition As Integer, ByVal wFlags As Long) As IntPtr
Private Declare Function GetSystemMenu Lib "user32" (ByVal hWnd As IntPtr, ByVal bRevert As Boolean) As IntPtr
Private Declare Function GetMenuItemCount Lib "user32" (ByVal hMenu As IntPtr) As Integer
Private Declare Function DrawMenuBar Lib "user32" (ByVal hwnd As IntPtr) As Boolean

Public Sub DisableCloseButton(ByVal hwnd As IntPtr)
Dim hMenu As IntPtr
Dim menuItemCount As Integer

hMenu = GetSystemMenu(hwnd, False)
menuItemCount = GetMenuItemCount(hMenu)
Call RemoveMenu(hMenu, menuItemCount - 1, MF_DISABLED Or MF_BYPOSITION)
Call RemoveMenu(hMenu, menuItemCount - 2, MF_DISABLED Or MF_BYPOSITION)
Call DrawMenuBar(hwnd)
End Sub

Then in the form.load() where you want to disable the close button just call function as below:

DisableCloseButton(Me.Handle)

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