I have a GUI application that needs to run long calculations (think a minute or more) and the way that it deals with this is by giving the calculation to a background worker. (this part is fine)
The question I have is if I do something like:
this.backgroundWorker.RunWorkerCompleted += new System.ComponentModel.RunWorkerCompletedEventHandler(this.doSomethingElse);
is doSomethingElse going to be run on the main UI thread or whatever in the thread pool the background worker ran on?
thank for any help you can provide.
It's going to be run in the same thread that BackgroundWorker is in, ie most usually the UI thread.
is doSomethingElse going to be run on the main UI thread
Yes, that is the main reason of being for a Backgroundworker. It has 3 events, only DoWork will be executed on a separate (ThreadPool) thread. Completed and ProgressChanged will be marshaled to the 'main' thread.
If the BackgroundWorker was created from the UI thread, then the RunWorkerCompleted event will also be raised on the UI thread.
If it was created from a background thread, the event will be raised on an undefined background thread.
See this post and this connect issue for more information.
https://stackoverflow.com/a/2806824/279999
http://connect.microsoft.com/VisualStudio/feedback/details/116930/backgroundworker-components-progresschanged-and-runworkercompleted-event-run-on-wrong-thread
