SYSK 42: A must-read article on BackgroundWorker class

I was going to write a post on the different ways to execute code asynchronously in .NET, the pros and cons.  You know, BeginInvoke, QueueUserWorkItem, the new BackgroundWorker class, the direct thread creation…  Before doing that, I wanted to check out if somebody has already done similar posting, and I came across this jewel from Julia Lerman with Michael Cambell’s (as a feedback).   Strongly recommended!  You can find it at http://blog.ziffdavis.com/devlife/archive/2005/12/21/39532.aspx.

 

Summary: it may be possible that RunWorkerCompleted event is fired on a thread different from the UI thread. To avoid exceptions when touching UI controls, use InvokeRequired and Invoke methods, if necessary.

Comments

• Anonymous
  January 17, 2006
  If I understand correctly, the issue she brought up was not resolved??
• Anonymous
  January 17, 2006
  The solution is to use InvokeRequired check, and call Invoke method, if necessary as described in http://msdn2.microsoft.com/en-us/library/ms171728.aspx
• Anonymous
  January 17, 2006
  Although doing the InvokeRequired check and invoking (if required) did the trick, the real problem brought up by my post is that the UI thread behavior that I was experiencing by calling the background worker programatically and NOT from the click of a UI control, was different than what the documentation suggests. It took me a lot of experimentation to figure out what I was doing "wrong" and WHY the invoke was necessary at all.