private void btn_Them_Click(object sender, EventArgs e)
        {
            Frm_KhachHangModified _frm_KhachHangModified = new Frm_KhachHangModified();

            _frm_KhachHangModified.ShowDialog();
            HienThiDuLieuLenDGV();
        }
 private void btn_Sua_Click(object sender, EventArgs e)
 {
     //var idCardSelected = Convert.ToInt32(txt_idCard.Text);
     if (!string.IsNullOrEmpty(tempIdCard))
     {
         Frm_KhachHangModified _frm_KhachHangModified = new Frm_KhachHangModified();
         _frm_KhachHangModified.tempIdCard     = tempIdCard;
         _frm_KhachHangModified.tempCusName    = tempCusName;
         _frm_KhachHangModified.tempCusAddress = tempCusAddress;
         _frm_KhachHangModified.tempCusGender  = tempCusGender;
         _frm_KhachHangModified.tempCusPhone   = tempCusPhone;
         _frm_KhachHangModified.Show(this);
         HienThiDuLieuLenDGV();
     }
     else
     {
         MessageBox.Show("Bạn chưa chọn thông tin khách hàng cần sửa!!!");
     }
 }