NullReference Exception is thrown while getting a callback channel

Posted by Yaroslav on Stack Overflow See other posts from Stack Overflow or by Yaroslav
Published on 2010-04-08T20:56:46Z Indexed on 2010/04/09 0:13 UTC
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Filed under:

nullreferenceexception

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wcf

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duplex

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contract

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callback

Hi!

I am trying to get along with WCF's duplex contracts. A code from this article

(http://msdn.microsoft.com/en-us/library/ms731184.aspx)

ICalculatorDuplexCallback callback = null; callback = OperationContext.Current.GetCallbackChannel();

throws a NullReferenceException. So how can i manage this?

Thanks for your attention!

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