private void btnAdd_Click(object sender, EventArgs e)
        {
            int i = 0;

            if (tbTeachCourseNo.Text.Trim().Equals(""))
            {
                MessageBox.Show("开课号不能为空", "提示");
                tbTeachCourseNo.Focus();
                return;
            }
            if (tbAmount.Text.Trim().Equals(""))
            {
                MessageBox.Show("学分不能为空", "提示");
                tbAmount.Focus();
                return;
            }
            if (tbTeacher.Text.Trim().Equals(""))
            {
                MessageBox.Show("学分不能为空", "提示");
                tbTeacher.Focus();
                return;
            }
            OpenCourse         oc  = new OpenCourse(tbTeachCourseNo.Text, cbCourseName.Text, tbTeacher.Text, int.Parse(tbAmount.Text), int.Parse(cbStartWeek.Text), int.Parse(cbEndWeek.Text));
            CourseManageAction cma = new CourseManageAction();

            cma.setOpenCourse(oc);
            if (isUpdate == false)
            {
                i = cma.addOpenCourse();
                if (i > 0)
                {
                    MessageBox.Show(string.Format("增加了{0}条记录", i));
                    foreach (Control ctrl in groupBox2.Controls)
                    {
                        if (!(ctrl is Label))
                        {
                            ctrl.Text = "";
                        }
                    }
                }
                else
                {
                    MessageBox.Show("添加不成功");
                }
            }
            else
            {
                i = cma.updateOpenCourse();
                if (i > 0)
                {
                    MessageBox.Show(string.Format("更新了{0}条记录", i));
                    this.Close();
                }
                else
                {
                    MessageBox.Show("更新不成功");
                }
            }
            this.Close();
        }