Page.Validate Null Reference Exception

Question

Hello all.

I have a bit of a problem I was wondering if you could help me.

I have the following little bit of code:

   protected void btnSubmit_Click(object sender, EventArgs e)
{
    Page.Validate("RadMaterial");
    Page.Validate("TopX");

    int max = 0;
    if (int.TryParse(txtbxHowMany.Text, out max))
    {

        GridView1.DataSource = this.GetMaterialData("123456",radTopx.SelectedItem.Value, "Primary", max);
        GridView1.DataBind();
    }

}

I have a couple of validation groups set up the first - if the click is made and the txtbxHowMany is not populated, a simple error is shown.

I also set up a validation group for the radiobutton list so that, should the user hit submit without checking a radiobutton, the required field validation should fire.

However, it is not firing. I am getting a "NullReferenceException was handled by user code."

My thinking is that because the radTopx.SelectedItem.Value is, well, null.

How would I go about getting around this little issue of mine? Again, apologies for what is most likely a ridiculously easy question.

Answer 1

Interesting the way you used Validate method.

See what msdn says about it.

http://msdn.microsoft.com/en-us/library/dwzxc386.aspx