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C# Win Form STA Thread is not supported

Hi,

I had a class I used that use's multiple threads. I have since added this class to a new windows from project. The code complies however at the line below,

WaitHandle.WaitAll(doneEvents);

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an NotSupportedException was unhandlewed is thrown. The error message is "WaitAll for multiple handles on a STA thread is not supported".

After reading some webpages on google, what I understand is that a window form run in single thread so cannot use multi threading without changing the attribute to MTA. Is this correct and how do I do such a thing? Also is this the same for WPF forms as I'm looking to learn about them very soon.

Thanks,
M
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Hello:
You can set the threaded apartment in Main method as an attribute. See this:
http://msdn.microsoft.com/en-us/library/system.stathreadattribute%28VS.71%29.aspx
And this:
http://msdn.microsoft.com/en-us/library/system.mtathreadattribute%28VS.71%29.aspx

Best regards.
High School Computer Science, Computer Applications, Digital Design, and Mathematics Teacher
CERTIFIED EXPERT
Top Expert 2009
Commented:
Couldn't you just iterate over them and call WaitOne() against each one?
            foreach (WaitHandle doneEvent in doneEvents)
            {
                doneEvent.WaitOne();   
            }

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Author

Commented:
Hi cubaman,

Thanks for the reply. Sorry those link's don't make a huge amount of sense to me. Am I able to change the attribute of a windows form & WPF to MTA from STA and make use of multithreading?

Cheers
M

Author

Commented:
Hi idle_mind,

Thanks for the reply. I think I have seen this as a viable soultion but wanted to know if I could change the attribute of either a windows form or WPF form to enable me to use to  WaitHandle.WaitAll method.

Cheers
M

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