Get thread to tell another thread when done in vb.net

It can be challenging when using threading to have a thread that is working tell another thread that its mission is complete. Here is how I did it.

Imports System.Threading
    ‘ Create an event that the thread can raise to let the calling thread know it is complete
    Public Event AccRunXrefCompletedHandler(ByVal sender As Object, ByVal e As EventArgs)
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        ‘ Add the event to this class
        AddHandler AccRunXrefCompletedHandler, AddressOf AccRunXrefCompleted
    End Sub
    ‘ Make this a class level variable so that you can keep a reference to the running thread
    ‘ this way if you want to terminate it you have the reference to do it with.
    Dim processAccRunXref As Thread
    ‘ I am using this button click event to start the thread
    Private Sub StartThreadProcess_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles StartThreadProcess.Click
        ‘ Create a new thread to run the process in
        processAccRunXref = New Thread(AddressOf AccRunXref)
        processAccRunXref.Start()
    End Sub
    Public Sub AccRunXref()
        ‘ Place your database code here
        ‘ This for loop is just to test with
        For idx As Integer = 0 To 100000
            Console.WriteLine(idx.ToString())
        Next
        ‘ Raise the event to let the caller know we have completed
        RaiseEvent AccRunXrefCompletedHandler(Me, EventArgs.Empty)
    End Sub
    Public Sub AccRunXrefCompleted(ByVal sender As Object, ByVal e As EventArgs)
        ‘ This event was raised by the thread to let us know it is done
        ‘ Do any processing here that needs to be don after the thread went to completion.
        MessageBox.Show("Thread Completed")
        processAccRunXref = Nothing
    End Sub
    ‘ This button click event will abort the running thread if you need to stop it
    Private Sub AbortThread_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles AbortThread.Click
        ‘ If the thread is alive then abort it and reset the class variable to nothing
        If processAccRunXref.IsAlive Then
            processAccRunXref.Abort()
        End If
        processAccRunXref = Nothing
    End Sub

 

Advertisements
  1. Leave a comment

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: