Asp.net user online exit update Implementation Code

The main problem is how to update the user's online list when the browser is closed.

The method circulating on the Internet is to keep sending ajax requests asynchronously. When no request is sent, you can determine that the user has closed the browser.
Copy codeThe Code is as follows:
Var x = 0;
Function myRefresh ()
{
Var httpRequest = new ActiveXObject ("microsoft. xmlhttp ");
HttpRequest. open ("GET", "test. aspx", false );
HttpRequest. send (null );
X ++;
If (x <60) // 60 times, that is, the actual Session expiration time is 30 minutes.
{
SetTimeout ("myRefresh ()", 30*1000); // 30 seconds
}
}
MyRefresh ();

Set in web. config:
<SessionState mode = "InProc" timeout = "1"> </sessionState>