PageRequestManager Multiple Asynchronous Postbacks Example

UpdatePanel 1 The submit button in this panel invokes a long running process or critical process on the server that we want to make sure does not get overridden by another asynchronous postback. Multiple clicks of the submit button in this panel or panel 2 are intercepted and canceled until the response from any existing postback from this panel is finished.

UpdatePanel 2 Clicking the submit button in this panel while an existing postback from panel 1 is still processing causes the panel 2 postback to be canceled. Clicking the submit button in this panel multiple times results in the default behavior, that is, last postback wins.