//获取全部课程
        private void btn_refreshCL_Click(object sender, EventArgs e)
        {
            CourseBusiness couBusiness = new CourseBusiness(this.studentModel.Sid);
            DataTable dt = new DataTable();
            //没有过滤条件
            if (this.cb_filter_week.Text=="全部周次" && this.cb_filter_section.Text=="全部时间")
            {
                dt = couBusiness.getAllCourse();
            }
            else
            {
                int section = 0, week = 0;
                switch (this.cb_filter_section.Text)
                {
                    case "周一(1)": section = 1; break;
                    case "周一(2)": section = 2; break;
                    case "周一(3)": section = 3; break;
                    case "周一(4)": section = 4; break;
                    case "周一(5)": section = 5; break;
                    case "周一(6)": section = 6; break;
                    case "周二(1)": section = 7; break;
                    case "周二(2)": section = 8; break;
                    case "周二(3)": section = 9; break;
                    case "周二(4)": section = 10; break;
                    case "周二(5)": section = 11; break;
                    case "周二(6)": section = 12; break;
                    case "周三(1)": section = 13; break;
                    case "周三(2)": section = 14; break;
                    case "周三(3)": section = 15; break;
                    case "周三(4)": section = 16; break;
                    case "周三(5)": section = 17; break;
                    case "周三(6)": section = 18; break;
                    case "周四(1)": section = 19; break;
                    case "周四(2)": section = 20; break;
                    case "周四(3)": section = 21; break;
                    case "周四(4)": section = 22; break;
                    case "周四(5)": section = 23; break;
                    case "周四(6)": section = 24; break;
                    case "周五(1)": section = 25; break;
                    case "周五(2)": section = 26; break;
                    case "周五(3)": section = 27; break;
                    case "周五(4)": section = 28; break;
                    case "周五(5)": section = 29; break;
                    case "周五(6)": section = 30; break;
                    case "周六(1)": section = 31; break;
                    case "周六(2)": section = 32; break;
                    case "周六(3)": section = 33; break;
                    case "周六(4)": section = 34; break;
                    case "周六(5)": section = 35; break;
                    case "周六(6)": section = 36; break;
                    case "周日(1)": section = 37; break;
                    case "周日(2)": section = 38; break;
                    case "周日(3)": section = 39; break;
                    case "周日(4)": section = 40; break;
                    case "周日(5)": section = 41; break;
                    case "周日(6)": section = 42; break;
                    case "全部时间": section = 0; break;
                }
                if (this.cb_filter_week.Text.ToString() == "1-16")
                {
                    week = 1;
                }
                else if (this.cb_filter_week.Text.ToString() == "1-8")
                {
                    week = 2;
                }
                else if (this.cb_filter_week.Text.ToString() == "9-16")
                {
                    week = 3;
                }
                else
                {
                    week = 0;
                }

                dt = couBusiness.getAllCourseWithFilter(week,section);

            }
            this.dataGridView1.AutoGenerateColumns = false;
            this.dataGridView1.DataSource = dt;
        }