private void button1_Click(object sender, EventArgs e)
        {
            DataTable  dt = new DataTable();
            HangHoaCtr hh = new HangHoaCtr();

            dt = hh.GetData2("Where MaNSX = '" + comboBox1.SelectedValue.ToString() + "'");
            if (dt.Rows.Count > 0)
            {
                dgvDanhSach.DataSource = dt;
            }
            else
            {
                MessageBox.Show("Không tìm thấy.", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                dgvDanhSach.DataSource = dt;

                dgvDanhSach.ClearSelection();
            }
        }
        private void button1_Click(object sender, EventArgs e)
        {
            DataTable  dt = new DataTable();
            HangHoaCtr hh = new HangHoaCtr();

            dt = hh.GetData2("Where TenMH like N'" + timkiem.Text + "%'");
            if (dt.Rows.Count > 0)
            {
                dgvDanhSach.DataSource = dt;
            }
            else
            {
                MessageBox.Show("Không tìm thấy.", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                dgvDanhSach.DataSource = dt;

                dgvDanhSach.ClearSelection();
            }
        }