private void TaoBangDSKhachHang()
        {
            DataTable dtKhachHang = busKhachHang.GetForDisplay();

            dtgvKhachHang.DataSource = dtKhachHang;
            dtgvKhachHang.Sort(dtgvKhachHang.Columns[0], ListSortDirection.Descending);
            dtgvKhachHang.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.Fill;
            dtgvKhachHang.AutoSizeRowsMode    = DataGridViewAutoSizeRowsMode.None;
        }