ScriptManager is a useful control. It manages script references, removes duplicates, enables localization and debug/release modes, enables script combining and makes client-side component-based development easier (components register their script dependencies with ScriptManager without the page developer having to know those dependencies). But one thing we should have anticipated was that this control would be interesting to developers who wish to use a different framework than the Microsoft Ajax Library.
Currently, ScriptManager isn't really usable without Microsoft Ajax because it includes the Microsoft library (without a simple way to disable it) and outputs some startup script to the page. We're looking at correcting that in future versions of the framework, but in the meantime I wanted to come up with a workaround.
The workaround is a simple control derived from ScriptManager and that enables the replacement of the MicrosoftAjax.js reference with a script of your choice:
<%@ Register Namespace="Bleroy" TagPrefix="asp" %> ...
The first thing the control does is set the default value for EnablePartialRendering to false. This suppresses the default reference to MicrosoftAjaxWebForms.js.
Then, it registers from Init two empty scripts with the type of the ScriptManager and names "AppInitialize" and "FrameworkLoadedCheck". This is a bit of magic that relies on knowledge of the names and types that ScriptManager uses to register its inline scripts.
Finally, it adds a ScriptReference with the Microsoft Ajax assembly and the "MicrosoftAjax.js" name but with a different path (the value of the new FrameworkPath property). This effectively replaces the Microsoft Ajax script reference with a script of your choice.
This should broaden developer choice in terms of client framework while keeping the great benefits of ScriptManager. Hope that helps.
Download it from here: http://weblogs.asp.net/bleroy/attachment/6374028.ashx