set parent dropdownlist of CascadingDropDown on server side

I have have 2 DropDownList controls with CascadingDropDown

I need set data to the first dropdownlist on server side if i do this, and when i get page on client side, the first DropDownList without data that i set on server side

Thanks for any help

//client

  &开发者_开发百科lt;asp:DropDownList ID="ddlAjaxManufacturer" runat="server">
    </asp:DropDownList>
    <ajaxToolkit:CascadingDropDown ID="CascadingDropDownManufacturer" runat="server"
        TargetControlID="ddlAjaxManufacturer" Category="Make" PromptText="....." ServicePath="../../Ajax.asmx"
        ServiceMethod="GetMakes"  />
    <asp:DropDownList BackColor="white" ID="ddlAjaxModel" runat="server">
    </asp:DropDownList>
    <ajaxToolkit:CascadingDropDown ID="CascadingDropDownModel" runat="server" TargetControlID="ddlAjaxModel"
        ParentControlID="ddlAjaxManufacturer" PromptText="....." ServiceMethod="GetModelsForMake"
        ServicePath="../../Ajax.asmx" Category="Model" />



//server


     ddlAjaxManufacturer.Items.Add(new ListItem("...", "", true));
                ddlAjaxManufacturer.Items.Add(new ListItem("11", "ford", true));
                ddlAjaxManufacturer.Items.Add(new ListItem("22", "bmw", true));

What your trying to do may work but in a different scenario. have you tried to use a web service to populate your dropdownlists? as far as i know CascadingDropDown works with a web service in order to populate the drop down buttons using ajax, did you see this video ?

http://www.asp.net/ajax/videos/use-aspnet-ajax-cascading-drop-down-control-to-access-a-database

it shows how CascadingDropDown extender works