How to perform a browser update for long running ASPX request to AJAX-enabled WCF service?

I've got a long running request on an ASPX page (.NET 3.5) to an AJAX-enabled WCF service. The set up basically works fine and I get the result back to my JavaScript callback after n seconds, but I'd like to know whether there is a way to keep the browser updated about the progress on the server while the process (开发者_如何学Pythoni.e. the webservice method) is running.

I've spent a while looking into this, but unfortunately I couldn't find any posts regarding my problem. As the AJAX request should basically be an XmlHttp request I assume that there might be a way to query for the status (and ideally even some status info, e.g. "n out of m entries processed").

Please let me know in case my question isn't clear enough, thanks in advance for your help.

G.

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One way is to poll the server at regular intervals and use a progress bar component. Polling can be accomplished by using a httphandler. Please check my reply here:

Need progressbar in GridView ASP.Net