ONJava.com: AJAX: How to Handle Bookmarks and Back Buttons

AJAX: How to Handle Bookmarks and Back Buttons
by Brad Neuberg
10/26/2005

This article presents an open source JavaScript library that finally brings bookmarking and back button support to AJAX applications. By the end of this tutorial, developers will have a solution to an AJAX problem that not even Google Maps or Gmail possesses: robust, usable bookmarking and back and forward behavior that works exactly like the rest of the Web.

“AJAX: How to Handle Bookmarks and Back Buttons” explains the significant issues that AJAX applications currently face with bookmarks and the back button; presents the Really Simple History library, an open source framework that solves these problems; and provides several working examples.

The principal discoveries of the framework presented in this article are twofold. First, a hidden HTML form is used to allow for a large transient session cache of client-side information; this cache is robust against navigation to and away from the page. Second, a combination of hyperlink anchors and hidden iframes is used to intercept and record browser history events, tying into the back and forward buttons. Both techniques are wrapped with a simple JavaScript library to ease development.