Execute server side code on close of a browser

To start with create a new asp.net page and add an instance of the ScriptManager to it. Now configure the ScriptManager to enable calling of page methods marked with WebMethod attribute.

The next step is to create a web method on the server. The method needs to be marked with the WebMethod attributte.

[WebMethod]
public static void BrowserCloseMethod()
{
    // Write Custom Code
    HttpContext.Current.Session.Abandon();
}   

Finally call the server method on closing the client browser window. Add a javascript method and call this method when the unload event for body of the browser is called.