drop down list

if i do the connection using sql data source...where i can add this coding...

i try to add this codes into page load area and it's nt working..

please guide me..

[code]

<form id="form1" runat="server">
    <div>
   
        <asp:DropDownList ID="dropDownList" runat="server"
            DataSourceID="SqlDataSource1" DataTextField="Value" DataValueField="Value"
            onselectedindexchanged="dropDownList_SelectedIndexChanged">
        </asp:DropDownList>
        <br />
        <br />
        <asp:DropDownList ID="DropDownList1" runat="server" AppendDataBoundItems="True"
            AutoPostBack="True" Height="34px"
            onselectedindexchanged="DropDownList1_SelectedIndexChanged" Width="111px">
        </asp:DropDownList>
   
        <br />
        <br />
   
    </div>
    <asp:SqlDataSource ID="SqlDataSource1" runat="server"
        ConnectionString="<%$ ConnectionStrings:AED_Panasonic_DataConnectionString %>"
        SelectCommand="SELECT [Value] FROM [UDFList]"></asp:SqlDataSource>
       
       
    </form>

[code]