FindControl returns null for a checkbox inside a RadGrid

[George]

Hello.

I need to check on each row of the grid if its checkbox is checked or not.

<tel:GridTemplateColumn HeaderStyle-Width="15px" UniqueName="gridTemplateColumnCheckbox">
                                    <ItemTemplate>
                                        <asp:CheckBox ID="chkItem" runat="server" AutoPostBack="false" CssClass="checkbox-item" />
                                    </ItemTemplate>
                                    <HeaderTemplate>
                                        <asp:CheckBox ID="chkSelectAll" runat="server" AutoPostBack="false" CssClass="checkbox-item-header" onclick="toggleCheckAll();" />
                                    </HeaderTemplate>
                                </tel:GridTemplateColumn>

[Doncho]

Hi George,

You can check out how to access Controls inside RadGrid and specifically in Template Columns in the following article:

• https://docs.telerik.com/devtools/aspnet-ajax/controls/grid/accessing-values-and-controls/server-side/accessing-controls#accessing-controls-in-template-column 

To be able to assist you more accurately I would ask you to share the complete markup declaration of the RadGrid along with all the relevant code-behind logic. That way I will be able to better understand the scenario and advise you accordingly.

[Neha]

Here's an example of how you can access the CheckBox control inside the ItemTemplate of the GridTemplateColumn

protected void RadGrid1_ItemDataBound(object sender, GridItemEventArgs e)
{
    if (e.Item is GridDataItem dataItem)
    {
        CheckBox chkItem = dataItem.FindControl("chkItem") as CheckBox;

        if (chkItem != null)
        {
            // Access or modify the CheckBox control here
            bool isChecked = chkItem.Checked;
        }
    }
}

You have the OnItemDataBound event handler wired up to the RadGrid. You can do this in the markup.

 

<telerik:RadGrid ID="RadGrid1" runat="server" OnItemDataBound="RadGrid1_ItemDataBound">
    <!-- Your RadGrid configuration -->
</telerik:RadGrid>

I hope it helps. For more information see the Doc Official Doc