浏览器再次关闭问题

Question

I've system that tracks users' work hours and workflow is like this:

If user logs in he/she is in and there are button buttons out/in buttons also log-out that handles out event.

The problem is when user closes the browser/tab, I cannot handle he or she is out. I've read about handling browser/tab close events, but, unfortunately, it's practically impossible. My next approach which is not more reliable, with cookies, I save the cookie when page onUnloads when page loads that cookie will be removed, and when user logs in I'll get cookies value which contains users' last activity and update the out time. But drawback is user may come to the site with different browsers/machines which doesn't have proper information about the last activity.

Answer 1

I personally would look at the session object. When that expires you can do whatever you need to do.

Answer 2

What you can do is a javascript call to the server every minute (using the Javscript timer functions as explained here: http://www.w3schools.com/js/js_timing.asp ).

But I am not sure your approach using the browser is correct. By definition, the browser/server connection is not connected. Cookies are a just a way to maintain connectivity because the HTTP protocol do not provide such features.

The second point is: you want to keep the track when the user connects from another browser. What about the user uses 2 different browsers in the same time? How do you detect the user (should he authenticates when the browser opens or can you rely on the IP address)? What I suggest is having a proper application to handle this: not a browser application. It should be not very complex to write one.

Well, applets and Adobe Flash could be a solution to enhance the capabilities in the browser...

Answer 3

Did you try adding a closeHandler via Window.addCloseHandler() . It's called when the user closes the window/tab. In the handler you could send a close message or something to the server.