How to assign a window close event handler?

Question

JavaScript

I open a new window:

window.popup = window.open('http://some.url', 'popup', 'width=572,height=570');

How to catch event, closing of the given window?

Answer 1

Try to do so, he recently dealt with this topic.

var tab = window.open('', '_blank');
tab.location;
tab.document.write('<body"> try to close </body>');
tab.window.onbeforeunload = function () {
        console.log ("Tab closed");
    }