Copy data from one Grid control to another Control in the same Grid

I have one Grid and I want to copy data from the datepicker to the  label control as shown in the code below. I am using the code below, but is not working. Any ideas will be welcome
<telerik:GridTemplateColumn HeaderText="New Start Date" UniqueName="bStartDate"  >                                                            <ItemTemplate>   <asp:Label runat="server" ID="bStartDate" Text=" ">   </asp:Label>    </ItemTemplate>                        ...