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();
}
}
}