There is really no way to do that, as client-side processing and server-side processing are 2 different things.

I posted this little control a while back that works asynchroneously and might help you out:
     http://forums.asp.net/1108756/ShowPost.aspx

Or you might take a look here for an AJAX solution:
     http://ajax.asp.net/docs/tutorials/PartialPageUpdateTutorials.aspx

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