Pre-Atlas, Generic "Original" Callback - Possible to Do with AJAX?

I'm using a number of callbacks with the original generic "Implements ICallbackEventHandler" techniques.

I built a set of sender/receiver/router functions on the JS side, and another on the VB side, so I can send structured messages between the client and server. I use this for getting context menus from the server, sending transactions to the server without full postback, detecting DB state, and so on.

I was wondering if there were built in tools in the new AJAX for doing this sort of thing...that is, for replacing the basic "Implements ICallbackEventHandler" function of passing strings back and forth.

Any guidance on this would be appreciated.

Thanks!

AJAX stands for Asynchronous Javascript And XML. AJAX is a web development technique used for creating interactive web applications. AJAX is the logical next step in the services-oriented architecture revolution. With AJAX, user interfaces from within the browser can use web services as their data source to store and retrieve information.

Asynchronous JavaScript and XML is not a technology in itself, but is a term that describes a "new" approach to using a number of existing technologies together, including: HTML or XHTML, Cascading Style Sheets, JavaScript, The Document Object Model, XML, XSLT, and the XMLHttpRequest object. When these technologies are combined in the AJAX model, web applications are able to make quick, incremental updates to the user interface without reloading the entire browser page. This makes the application faster and more responsive to user actions.

You can try to take a look at this reading about Ajax - http://www-128.ibm.com/developerworks/web/library/wa-ajaxintro1.html
Wish the above can give you some helps.
Try to take a look at this blog about ICallbackEventHandler vs Ajax - http://staff.develop.com/ballen/blog/PermaLink.aspx?guid=c35c43f6-5686-40ee-9752-8095a848d821
Wish this can help you.

Heh, I am also thinking of this?

All I see on the extenders for example is that they are not self-contained, or are able to be, when talking to the server.

For instance, I made a control called CallbackValidator which inherits from BaseValidator and behaves just like a CustomValidator, just that it uses ICallbackEventHandler.

I have yet to see that ASP.NET AJAX supports this, because all I see is that you have to expose a webservice and reference that via URL. Why?

This makes it tedious to use the same control which should be self-contained in multiple projects, because you have to set that asmx stuff up.

Am I missing something here?