Nested datagrid in a repeater. Reading row values

[Maziar Aflatoun]

Hi everyone,

I have a datagrid that I create inside a Repeater at runtime. I have
defined a checkbox beside each row so that users can select multiple rows.
<asp:datagrid id="dgProducts" HorizontalAlign="Center"
AutoGenerateColumns="false" CellPadding="2"
runat="server" >
......
<asp:TemplateColumn HeaderText="" HeaderStyle-Width="20">
<ItemStyle HorizontalAlign="Center"></ItemStyle>
<ItemTemplate>
<asp:CheckBox ID="cbxProduct" Runat="server"
AutoPostBack="False"></asp:CheckBox>
</ItemTemplate>
</asp:TemplateColumn>

Just below my datagrid I have a button (Add button). I want to read the
values of all the checkboxes in my dynamically created datagrid. But it
keeps complaining that

System.NullReferenceException: Object reference not set to an instance of an
object.
for that Line Response.Write...

This is the code
private void btnAddProducts_Click(object sender, System.EventArgs e)
{
DataGrid dgProducts = this.Page.FindControl("dgProducts") as DataGrid;
Response.Write("Rows: " + dgProducts.Items.Count);
}

Can someone please help me with this?

Thank you
Maz