Problem using CascadingDropDown control from AjaxContro lToolkit on sharepoint 2010

I tried to use CascadingDropDown control开发者_如何学C on a sharepoint visual webpart including the project as a web service. Of course it didn´t work as i expected. Has anyone used this control in a sharepoint webpart or knows how to implement a cascading drop down using Ajax ?

I would post up the links to the forum threads at least for my own personal reference.

http://social.msdn.microsoft.com/Forums/en-US/sharepointcustomization/thread/552e69f8-4fb8-4019-96e4-1109e305732b/

http://social.msdn.microsoft.com/Forums/en-US/sharepointcustomization/thread/76c765cf-f3ce-4930-8b44-e7a75db6f405

thanks for your answer i will review that approach to, but well. . what a did wrong was write inside the update panel a form tag

<asp:UpdatePanel ID="AjaxSampleUpdatePanel" runat="server">
    <ContentTemplate>
        <form></form>
    </ContentTemplate>
</asp:UpdatePanel>

but that was making the problem so i just change the form tag ubication like this

<form>
   <asp:UpdatePanel ID="AjaxSampleUpdatePanel" runat="server">
        <ContentTemplate>

        </ContentTemplate>
    </asp:UpdatePanel>
</form>

and that make the code works!!