protected void GridView1_SelectedIndexChanged(object sender, EventArgs e) { string maTacGia = GridView1.SelectedRow.Cells[0].Text; tg = cn.GetTacGiaByID(maTacGia); if (tg != null) { txtMaTacGia.Text = tg.MaTacGia; txtTenTacGia.Text = tg.TenTacGia; } }