Sample Download : http://code.msdn.microsoft.com/CSASPNETDetectBrowserCloser-602e8486
As we know, HTTP is a stateless protocol, the browser doesn't keep connecting to the server. When user try to close the browser using alt-f4, browser close(X) and right click on browser and close, it's not possible to tell the server that the browser is closed. The sample demonstrates how to detect the browser close event with iframe.
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