Sample Download : http://code.msdn.microsoft.com/How-to-Detect-the-Web-737ef524
As we know, HTTP is a stateless protocol, so the browser doesn’t keep connecting to the server. When users try to close the browser using alt-f4, browser close(X) and right click on browser and close, all these methods are working fine, but it’s not possible to tell the server that the browser is closed.The sample demonstrates how to detect the browser close event.It includes two parts:1 Send ajax call every 20 seconds, to tell the server side that the page is still open.2 Send ajax call when the browser is closed.
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