How to detect/track postback in javascript?

Question

How to detect/track/check postback in javascript(e.g in asp.net Page.isPostBack())? Any suggestion?

Answer 1

You can only keep track of the postback if you are using AJAX requests or have a hidden field of some sort that the javascript reads on page load. Otherwise the page is regenerated and all POST data is lost; as you would expect and hope.