private void btnHienThiDanhSach_Click(object sender, EventArgs e) { if (cmbNamHoc.SelectedValue != null && cmbLop.SelectedValue != null && cmbHocKy.SelectedValue != null) { m_HocSinhCtrl.TimKiemHocSinh_NamHoc_HocKy_Lop(cmbNamHoc, cmbHocKy, cmbLop, dGVKetQuaTimKiem, bindingNavigatorKetQuaTimKiem); } txtHoTen.ResetText(); }