Dynamic Script Loading

An update to "Include JS File from JS"

// then bind the event to the callback function

// there are several events for cross browser compatibility

script.onreadystatechange = callback;

script.onload = callback

In IE6, there is a possibility of the callback function being called twice. This is because script.onreadystatechange could be called in the several states:

0	uninitialized
1	loading
2	loaded
3	interactive
4	complete

You can include a handler to only callback when script is complete.

script.onreadystatechange= function () { if (this.readyState == 'complete') callback();}

The problem with this is that in IE7, you either get a 'loaded' event or 'completed' event. 

I would suggest using the JQuery method $.getScript("file.js", function() {}); or add the callback in the JS file that u are adding dynamically.

Reference: http://unixpapa.com/js/dyna.html