Cascading DropdownList Disable

Hello

I have cascading Dropdownlist gets populated with a Webservice and I need to disable that dropdownlist. I tried adding a handler but no use.

on aspx page

<script type="text/javascript">

 function pageLoad(sender, args) {
            $find("cddl").add_populated(DisableDDL);
        
        }

        function DisableDDL() {
          
            $get("ddlCountry").disabled = true;

</script>

//Control on PAGE

<tr><td> Select Country:</td><td>
           <asp:DropDownList ID="ddlCountry" runat="server"></asp:DropDownList>
           <asp:CascadingDropDown ID="CountryCascading" runat="server" Category="Country"  BehaviorID="cddl"
            TargetControlID="ddlCountry" LoadingText="Loading Countries..." PromptText="Select Country"
            ServiceMethod="BindCountry" ServicePath="testServ.asmx">
       </asp:CascadingDropDown> </td></tr>

I don't know what I'm missing. I really appreciates any insight.

Thanks

Rao