c# - validate textbox if empty and if number entered

Question

private void btnsave_Click(object sender, EventArgs e)
{
   if (txtfname.Text == "" )
   {
      MessageBox.Show("Please enter your First Name");
      txtfname.Focus();
   }
}

I want to validate a textbox such that a person cannot leave it blank nor can they add numbers. Do I have to write an "else if" statement or is there any operator that I can use to put it all in the same if statement.

Answer 1

The operator you can use is ||

string fName = txtfname.Text;
if (string.IsNullOrWhiteSpace(fName) || fName.Any(Char.IsDigit))
{
    MessageBox.Show("Please enter your First Name without digits");
    txtfname.Select();
}