private void BtnDelete_Click(object sender, EventArgs e)
{
c.ContactId = Convert.ToInt32(textBoxContactId.Text);
bool success = c.Delet(c);
if (success == true)
{
MessageBox.Show("Contact delet successfully !");
DataTable dt = c.Select();
dgvContactList.DataSource = dt;
clear();
}
else
{
MessageBox.Show("Faild to delet!");
}
}