/// <summary>        /// 得到一年中的某周的起始日和截止日        /// 年 nYear        /// 周数 nNumWeek        /// 周始 out dtWeekStart        /// 周终 out dtWeekeEnd        /// </summary>        /// <param name="nYear"></param>        /// <param name="nNumWeek"></param>        /// <param name="dtWeekStart"></param>        /// <param name="dtWeekeEnd"></param>        private void GetWeek(int nYear, int nNumWeek, out   DateTime dtWeekStart, out   DateTime dtWeekeEnd)        {            DateTime dt = new DateTime(nYear, 1, 1);            dt = dt + new TimeSpan((nNumWeek - 1) * 7, 0, 0, 0);            dtWeekStart = dt.AddDays(-(int)dt.DayOfWeek + (int)DayOfWeek.Monday);            dtWeekeEnd = dt.AddDays((int)DayOfWeek.Saturday - (int)dt.DayOfWeek + 1);        }

/// <summary>        /// 求某年有多少周        /// 返回 int        /// </summary>        /// <param name="strYear"></param>        /// <returns>int</returns>        private int GetYearWeekCount(int strYear)        {            System.DateTime fDt = DateTime.Parse(strYear.ToString() + "-01-01");            int k = Convert.ToInt32(fDt.DayOfWeek);//得到该年的第一天是周几             if (k == 1)            {                int countDay = fDt.AddYears(1).AddDays(-1).DayOfYear;                int countWeek = countDay / 7 + 1;                return countWeek;            }            else            {                int countDay = fDt.AddYears(1).AddDays(-1).DayOfYear;                int countWeek = countDay / 7 + 2;                return countWeek;            }        }