Ajax combo box data fill in ASP.NET application

[weeraa]

I'm Developing application using ASP.NET and VB.NET. It is used Ajax controls as well. I added dropdownlist (Standard controller) and databind to it. It is working well. But if i added Ajax combo box, it is not working. (It means data not filling to combobox) No any errors showing.

This is my ASP code

    <asp:UpdatePanel ID="UpdatePanel1" runat="server">
       <ContentTemplate>
           <asp:ComboBox ID="ComboBox1" runat="server" AppendDataBoundItems="True"
       AutoCompleteMode="SuggestAppend" AutoPostBack="True" MaxLength="10">
           </asp:ComboBox>
       </ContentTemplate>
      </asp:UpdatePanel>

This is my VB code in form load event

ComboBox1.DataSource = ds.Tables(0)
ComboBox1.DataValueField = "PT_ID"
ComboBox1.DataTextField = "PT_PartName"
ComboBox1.DataBind()

In above code, dataset (defined as ds) has values. If i added Dropdownlist controller name instead of combobox1, data fill to the dropdownlist.

What's wrong with my code. no any errors are showing...

Other details.
VS2008
.NET frame work 3.5
AjaxControlToolkit.Binary.NET35

[LastMitch]

What's wrong with my code. no any errors are showing...

I'm no familiar with VB. But for your combo box code you should have included something this which I notice you didn't post it so I assume you don't have it bind:

http://asp-net-example.blogspot.com/2011/02/ajax-combobox-how-to-data-bind-combobox_05.html

[BMXDad]

Debug your code and make sure its being called.