private void btnDelete_Click(object sender, EventArgs e)
 {
     if (dtvCreditCard.CurrentRow != null)
     {
         if (MessageBox.Show("Tem certeza que deseja apagar este item ?", "", MessageBoxButtons.YesNo) == DialogResult.Yes)
         {
             CreditCard deleteCredCard = (CreditCard)dtvCreditCard.SelectedRows[0].DataBoundItem;
             ctr.Remove(deleteCredCard);
             creditCards.Remove(deleteCredCard);
         }
     }
 }