Creating controls from Async Callbacks

Posted on 2005-03-31
Medium Priority
Last Modified: 2012-06-27

Hey Experts,

I am looking for some more information about Async Callbacks.

Do they run on the ui thread that the Async method was called from or do they run on a seperate thread?

I am assuming that they run on a seperate thread because if I attempt to create windows controls and display it doesn't work.  Assuming this is correct how would you get the main ui thread to create something for you after a callback has fired?

Thanks in advance!

Question by:ACanadian
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Expert Comment

ID: 13675212
You want to create a control, and add it to the form?
LVL 10

Accepted Solution

eternal_21 earned 1000 total points
ID: 13675255
If I understand you right, you can use this code in your form class:

  private delegate void AddControlHandler(Control control);

  public void InvokeAddControl(Control control)
    Invoke(new AddControlHandler(AddControl), new object[] {control});

  private void AddControl(Control control)

And then from your Async callback, or any other thread, you can do:


where 'newControl' is the new control that you are adding to the form (initialized, and properties such as Location set, etc.).

Author Comment

ID: 13676941

Thank you very much!

I needed to know that Invoke calls the function on the owning thread.

Thanks again... perfect answer.

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