private void user_name_txb_Leave(object sender, EventArgs e) { if (user_type_cmb.SelectedIndex != 2) { if (string.IsNullOrEmpty(user_name_txb.Text) == true) { errorProvider3.SetError(this.user_name_txb, "Enter a Username"); } else if (rs.IseusernameAva(user_name_txb.Text) == 1) { errorProvider3.SetError(this.user_name_txb, "username is Allready registered"); } else { errorProvider3.Clear(); } } }