private void btSuaTK_Click(object sender, EventArgs e) { if (txtTenTK.Text == "" || txtMaukhau.Text == "" && cbNhomquyen.Text == "") { MessageBox.Show("Khong co du lieu"); return; } TaiKhoan tk = new TaiKhoan(txtTenTK.Text, txtMaukhau.Text, cbNhomquyen.Text); try { cnb.UpdataTaiKhoan(tk); } catch (Exception p) { MessageBox.Show(p.ToString()); } }