DropdownList Postback with RadGrid

[william]

Good day,

I have the following. I have a dropdownlist control in an Insert view mode. I need that my dropdownlist populates a pair of textbox controls from the database in the same view. I'm using the ddlEntityTypeFilter_SelectedIndexChanged event in order to do it. However I have got an error during the process since the Texbox control is returning a null value then I haven't been able to populate the texbox controls. Actually I need to populate Encargado2 and Email2 textbox controls.

Here is the aspx file:

<telerik:GridTemplateColumn  UniqueName="Nombre" DataField="Nombre" HeaderText="Nombre del Area"
             ForceExtractValue="InEditMode" ConvertEmptyStringToNull="true" >
               <EditItemTemplate>
                    <asp:DropDownList CssClass="dropdownlist" ID="ddlNombre" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ddlEntityTypeFilter_SelectedIndexChanged"></asp:DropDownList>
                        <asp:Label ID="LabelNombre" runat="server" Text='<%#Eval("Nombre") %>'></asp:Label>
                </EditItemTemplate>
                    <ItemTemplate>
                    <asp:Label ID="LabelNombre" runat="server" Text='<%#Eval("Nombre") %>'></asp:Label>
                </ItemTemplate>
            </telerik:GridTemplateColumn>

 <telerik:GridBoundColumn UniqueName="Encargado" DataField="Encargado" HeaderText="Encargado">
      </telerik:GridBoundColumn>
        <telerik:GridBoundColumn UniqueName="Email" DataField="Email" HeaderText="Email">
      </telerik:GridBoundColumn>

      <telerik:GridTemplateColumn  UniqueName="Encargado2" DataField="Encargado2" HeaderText="Encargado2"
             ForceExtractValue="InEditMode" ConvertEmptyStringToNull="true" Visible="false" >
          <%--   <ItemTemplate>
                    <asp:Label ID="LabelEncargado2" runat="server" Text='<%#Eval("Encargado2") %>'></asp:Label>
                </ItemTemplate>--%>
                  <EditItemTemplate>
                    <asp:TextBox  ID="TextBoxEncargado2" runat="server"></asp:TextBox>
                        <asp:Label ID="LabelEncargado2" runat="server" Text='<%#Eval("Encargado2") %>'></asp:Label>
                </EditItemTemplate>
            </telerik:GridTemplateColumn>

         <telerik:GridTemplateColumn  UniqueName="Email2" DataField="Email2" HeaderText="Email2"
             ForceExtractValue="InEditMode" ConvertEmptyStringToNull="true" Visible="false" >
                <%--    <ItemTemplate>
                    <asp:Label ID="LabelEmail2" runat="server" Text='<%#Eval("Email2") %>' ></asp:Label>
                </ItemTemplate>--%>
                 <EditItemTemplate>
                    <asp:TextBox  ID="TextBoxEmail2" runat="server"></asp:TextBox>
                        <asp:Label ID="LabelEmail2" runat="server" Text='<%#Eval("Email2") %>'></asp:Label>
                </EditItemTemplate>
            </telerik:GridTemplateColumn>

And the code behind:

protected void ddlEntityTypeFilter_SelectedIndexChanged(object sender, EventArgs e)

{    

    DropDownList dropdown = (DropDownList)sender;

    string value = dropdown.SelectedValue;

    SpecialTablesController sp = new SpecialTablesController();

    GridEditFormInsertItem edititem = (GridEditFormInsertItem)dropdown.NamingContainer;

    TextBox TextBoxID = (TextBox)edititem.FindControl("Encargado2"); -> TextboxID is null     

    Dependencia obj = sp.GetDependencyValues(dropdown.SelectedValue);

    TextBoxID.Text = obj.Encargado;-> I got the error here NullReferenceException


    TextBoxID.Text = obj.EMail;      

 

}

Any suggestion?

Thanks in advance
William

[Princy]

Hello William,

You need to use the ID of the TextBox (here it is TextBoxEncargado2) to access it from code behind.

C#:

protected void ddlEntityTypeFilter_SelectedIndexChanged(object sender, EventArgs e)
{
    DropDownList dropdown = (DropDownList)sender;
    GridEditFormInsertItem edititem = (GridEditFormInsertItem)dropdown.NamingContainer;
    TextBox TextBoxID = (TextBox)edititem.FindControl("TextBoxEncargado2"); // accessing TextBox
}

Thanks,
Princy.

[william]

Thanks a lot! It works.