Using beforeunload to execute task before page exit

I'm trying to get an action executed before page leave, this requires 开发者_Python百科a GET request being executed.

I would like to give the GET request at least 50-100ms in order to get the request forwarded to the web server.

I'm capturing the beforeunload action using:

$(window).bind('beforeunload', function() {
    send_data();
});

Any tips?

You have the highest chance to get your request sent if you make it synchronous (async: false in the $.ajax() options if you are using jQuery).

But you cannot be sure it always gets through..

You should prevent default action with event.preventDefault().

Note that not every browser support beforeunload