Asynchronous webservice call, UI thread issue in asp.net

[krishna]

Hi,
I am calling a webmethod asynchronously using a callback
delegate. I have implemented begin and end webmethods
inside my webservice class.
When I step into my client-side callback delegate, I see
the right results returned by my web method. But as this
callback delegate is getting executed on a seperate
thread, I am not able to populate my UI element with
result of the web service call. The same code works fine
if the client is windows forms app. Also windows form
controls implement ISynchronizeInvoke interface to
marshal results to the UI thread. How can I do this in
web forms? If I wait for the webmethod results on the UI
thread by blocking it, I can work with UI elements. But I
don't prefer to block the UI thread while my web method
is being executed.
Thanks for any feedback,
Krishna

 

[Bill Safcik]

Hi Krishna,

Basically calling the web service asynchronously will not work from a web
form.
There is no guarantee that the thread that the initial request comes in on
will stay around until the other thread that is calling the webservices
webmethods. So it may not have anything to call back into.

You could do this synchronously on 1 thread, so the calling thread will be
blocked until the web service returns the data that needs to be populated
in the UI.

Thank you,

Bill Safcik

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