AAdd a second UpdatePanel to the page. Set it to trigger based on the first Update-Panel. Set the contents of this UpdatePanel to read “Processing, please wait.”
BAdd an UpdateProgress control to the UpdatePanel. Set its DisplayAfter attribute to 5,000. Set its ProgressTemplate contents to read “Processing, please wait.”
CAdd a ProgressBar control to the page. Write code on the server to call back to the client asynchronously to update the ProgressBar control after five seconds.
DCreate a hidden <div> tag on your page that contains the text “Processing, please wait.” Set the <div> tag’s ID to match that of the UpdatePanel. Set the Update-Panel control’s Interval property to 5,000.