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Ajax Memory Leaks Explained

Douglas Crawford has a great site about JavaScript (the world's most misunderstood, yet most popular, programming language) where he explains memory leaks. If you create HTML through script (as is typical with AJAX applications)-- your application *has* memory leaks in IE if you have click events in the HTML and you don't remove them. Check out his article on memory leaks which include sample demo pages. The leak is only a factor for IE users-- and yes, it's an issue in IE7/8.

To clean up the memory leak bug, you MUST purge the DOM elements of functions before removing them from the DOM. Here's a code sample, gratuitously ~~stolen~~ borrowed from Douglas himself:

////From crockford.com:
function purge(d) {
    var a = d.attributes, i, l, n;
    if (a) {
        l = a.length;
        for (i = 0; i < l; i += 1) {
            n = a.name;
            if (typeof d === 'function') {
                d = null;
            }
        }
    }
    a = d.childNodes;
    if (a) {
        l = a.length;
        for (i = 0; i < l; i += 1) {
            purge(d.childNodes);
        }
    }
}