private void btn_Start_Click(object sender, EventArgs e)
        {
            if (dgv_Results.SelectedRows == null && dgv_Results.Rows.Count > 0)
            {
                dgv_Results.Rows[0].Selected = true;
            }

            DataGridViewRow gridView = dgv_Results.SelectedRows[0];

            TestInfo testInfo = new TestInfo()
            {
                CourseCode   = cmb_Course.SelectedValue.ToString(),
                CourseName   = cmb_Course.Text,
                StudentCode  = lbl_StudentCode.Text,
                StudentName  = lbl_StudentName.Text,
                TimesStep    = int.Parse(gridView.Cells[5].Value.ToString()),
                TotalTime    = int.Parse(gridView.Cells[7].Value.ToString()),
                DateExam     = Convert.ToDateTime(gridView.Cells[4].Value),
                ClassName    = lbl_ClassName.Text,
                listQuestion = GetListQuestion()
            };

            if (Program.mGroup.Equals("SINHVIEN"))
            {
                if (SqlRequestFunction.HasBeenExamined(testInfo.StudentCode, testInfo.CourseCode, testInfo.TimesStep))
                {
                    MessageBox.Show("Bạn đã thi môn này rồi. Vui lòng kiểm tra lại thông tin."
                                    , "Đã kiểm tra."
                                    , MessageBoxButtons.OK
                                    , MessageBoxIcon.Information);
                    return;
                }
            }

            TestExam testExam = new TestExam(testInfo);

            testExam.ShowDialog();
        }