private void btnTIm_Click(object sender, EventArgs e) { if (txtTenNhanVien.Text != "") { try { QuanLyBanHangQuaMangDataContext dbs = new QuanLyBanHangQuaMangDataContext(); dgvNV.DataSource = dbs.SP_TimNV(txtTenNhanVien.Text.Trim()); } catch (Exception err) { MessageBox.Show(err.Message); } } else { MessageBox.Show("Chưa gõ tên"); } }