Question

i have:

<asp:TemplateField HeaderText="Choose Option">
<ItemTemplate>
 <asp:RadioButtonList ID="rdbChoice" runat="server" RepeatDirection="Horizontal">
 <asp:ListItem Value="A">A</asp:ListItem>
 <asp:ListItem Value="B">B</asp:ListItem>
 <asp:ListItem Value="C">C</asp:ListItem>
 </asp:RadioButtonList>
</ItemTemplate>
</asp:TemplateField>

In the button click, I want to get the RadioButtonList.SelectedValue. I try:

protected void btnsubmit_Click(object sender, EventArgs e)
 {
   for (int i = 0; i <= gvQuestion.Rows.Count - 1; i++)
        {
            RadioButtonList rd1 = (RadioButtonList)gvQuestion.FindControl("rdbChoice");
            string rd = rd1.SelectedValue.ToString();
        }
 }

But i get an error Object reference not set to an instance of an object. What is my mistake?

Answer 1

The NamingContainer of your RadioButtonList is the GridViewRow not the GridView, so this works:

for (int i = 0; i <= gvQuestion.Rows.Count - 1; i++)
{
   RadioButtonList rdbChoice = (RadioButtonList)gvQuestion.Rows[i].FindControl("rdbChoice");
   string rd = rdbChoice.SelectedValue;
}

Keep in mind that FindControl does not look recursively into child container, it only searches the current NamingContainer for the given ID.