1.課程表框架的構建：

2.專案輸入框架的構建：

3.通過演算法的構建判斷當前是開學第幾周

     1）程式碼：

        public static int Excute(DateTime dTime)
        {
            try
            {
                //確定此時間在一年中的位置
                var dayOfYear = dTime.DayOfYear;
                
 
//本學期第一天
                var tempDate = new DateTime(dTime.Year, 1, 1);
                //確定第一天
                var tempDayOfWeek = (int)tempDate.DayOfWeek;
                tempDayOfWeek = tempDayOfWeek == 0 ? 7 : tempDayOfWeek;
                //確定星期幾
                var index = (int)dTime.DayOfWeek;
                index 
 
= index == 0 ? 7 : index;
                //當前周的範圍
                DateTime retStartDay = dTime.AddDays(-(index - 1));
                DateTime retEndDay = dTime.AddDays(7 - index);
                //確定當前是第幾周
                var weekIndex = (int)Math.Ceiling(((double)dayOfYear + tempDayOfWeek - 1) / 7);
                
 
if (retStartDay.Year < retEndDay.Year)
                {
                    weekIndex = 1;
                }
                return weekIndex;
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }
    


        private void dateTimePicker1_ValueChanged(object sender, EventArgs e)
        {
            dateTimePicker2.Visible = false;
            button2.Visible = false;
            label3.Visible = false;
           DateTime dt = DateTime.Parse(dateTimePicker2.Text);  //獲取當前時間
            DateTime date = DateTime.Parse(dateTimePicker1.Text);
            string hours = date.Hour.ToString();
            string minute = date.Minute.ToString();
            string second = date.Second.ToString();
            int zhoushu = Excute(date);
            int zhoushu1 = Excute(dt);
            MessageBox.Show("本週是開學後第" + Convert.ToString(zhoushu - zhoushu1+1)+"周");
            label2.Visible = true;
            label2.Text = "第" + Convert.ToString(zhoushu - zhoushu1 + 1) + "周";
        }

2）執行結果截圖：