UpdateProgress control shows the status information for the progress of the download occurring during the partial-page rendering in the UpdatePanel. The page can contain multiple UpdateProgress controls. Each one can be associated with a different UpdatePanel control. Alternatively, you can use one UpdateProgress control and associate it with all the UpdatePanel controls on the page.
You can place UpdateProgress control either inside or outside the UpdatePanel controls. The following Asp.Net program shows how to an UpdateProgress control waits for completion of the task and during this waiting time it shows a .gif file as waiting message.
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