private void btnTimKiemKH_Click(object sender, EventArgs e) { switch (typeCheck) { case 1: { DTO_Customer emp = new DTO_Customer(Convert.ToInt32(txtbtimkiemkh.Text)); DataTable dt = new DataTable(); BUS_Customer em = new BUS_Customer(); dt = em.SearchByMaKH(emp); dgvtimkiem.DataSource = dt; break; } } }