public void ResetSP()
        {
            txtMaSP.ResetText();

            txtTenSP.Properties.DataSource    = spBLL.LayDanhSach();
            txtTenSP.Properties.DisplayMember = "Ten";
            txtTenSP.Properties.ValueMember   = "MaSP";

            txtLSP.Properties.DataSource    = lspBLL.LayDanhSach();
            txtLSP.Properties.DisplayMember = "Ten";
            txtLSP.Properties.ValueMember   = "MaLSP";

            txtSoLuong.ResetText();
        }
 public void CapNhat()
 {
     gridControl1.DataSource = lspBLL.LayDanhSach();
 }