find costum control in filter template

[mohamadreza]

I'm trying to filter a column of a grid table using a custom persian datepicker control that mentioned in Grid - Filter Templates demo. but it couldn't find that custom date picker in javascript code , so the alert function returns "null".

plz help.

<telerik:RadGrid RenderMode="Lightweight" ID="RadGrid2" ShowStatusBar="true" runat="server" AllowPaging="True"                    PageSize="5" DataSourceID="sds_RadGrid_Records" AllowFilteringByColumn="true" >
                    <MasterTableView Width="100%" AutoGenerateColumns="false" DataKeyNames="AutoCnt"                        DataSourceID="sds_RadGrid_Records">
                        <Columns>
                            <telerik:GridBoundColumn ItemStyle-Width="30px" UniqueName="RegNumber" ShowFilterIcon="false" DataField="RegNumber" HeaderText="RegNumber"  CurrentFilterFunction="Contains" AutoPostBackOnFilter="true" FilterDelay="2000">
                            </telerik:GridBoundColumn>

                            <telerik:GridBoundColumn ItemStyle-Width="30px" UniqueName="Barid_ID" DataField="Barid_ID" HeaderText="Barid_ID"
                                CurrentFilterFunction="Contains" AutoPostBackOnFilter="true" >
                            </telerik:GridBoundColumn>

                            <telerik:GridBoundColumn ItemStyle-Width="30px" ShowFilterIcon="false" UniqueName="People" DataField="People" HeaderText="People"
                                CurrentFilterFunction="Contains" AutoPostBackOnFilter="true" FilterDelay="10000">
                            </telerik:GridBoundColumn>

                            <telerik:GridDateTimeColumn  DataType="System.DateTime" UniqueName="RegDate" DataField="RegDate" HeaderText="RegDate">
                            <%--<ItemTemplate>
                                <asp:Label ID="Label32" runat="server" Text='<%# Fadate.GetFaDate_WithEslash(Eval("RegDate")) %>'></asp:Label>
                            </ItemTemplate>--%>
                                <FilterTemplate>
                                    <telerik:RadLabel runat="server" AssociatedControlID="txt_Filter_RegDate_From" Text="From" Style="padding-left: 5px;"></telerik:RadLabel>
                                    <rhp:DatePicker ID="txt_Filter_RegDate_From" runat="server" OnUpdate="FromDateSelected" Width="80px"></rhp:DatePicker>


                                    <telerik:RadLabel runat="server" AssociatedControlID="txt_Filter_RegDate_To" Text="To" Style="padding-left: 5px;"></telerik:RadLabel>
                                    <rhp:DatePicker ID="txt_Filter_RegDate_To" runat="server" Width="80px"></rhp:DatePicker>


                                  <telerik:RadScriptBlock ID="RadScriptBlock2" runat="server">
                                    <script type="text/javascript">
                                        function FromDateSelected(calendar) {
                                            var tableView = $find("<%# ((GridItem)Container).OwnerTableView.ClientID %>");
                                           var ToPicker = $find('<%# ((GridItem)Container).FindControl("txt_Filter_RegDate_To").ClientID %>');
                                            alert(ToPicker);
                                        }
                                    </script>
                                        </telerik:RadScriptBlock>
                                </FilterTemplate>
                            </telerik:GridDateTimeColumn>

                        </Columns>
                    </MasterTableView>
                    <ClientSettings AllowKeyboardNavigation="true" EnablePostBackOnRowClick="false">
                        <Selecting AllowRowSelect="true"></Selecting>
                    </ClientSettings>
                    <PagerStyle Mode="NextPrevAndNumeric"></PagerStyle>
                </telerik:RadGrid>

[mohamadreza]

no one could help?!