Cascadingdropdown with database

I was reading about cascadingdropdown and i see an example to work with a database with webservice but my application architecture don`t permit do that. i have to call another class first. well there an example of cascadingdropdown to call a metod on the page in place webservice?

regardsThe CascadingDropDown sample page that comes with the Toolkit shows how to use it with both a web service and a page method.