/// <summary>

        /// 获取startdate到enddate之间的时长，剔除8-12 14-18这2个时间段。返回总秒

        /// </summary>

        /// <param name="startdate"></param>

        /// <param name="enddate"></param>

        /// <returns></returns>

        public static string getShiChang(string startdate, string enddate)

        {



            DateTime startTime = Convert.ToDateTime(startdate);

            DateTime endTime = Convert.ToDateTime(enddate);

            TimeSpan ts = new TimeSpan();

            double shichang = 0;

            double shichang1 = 0;

            double shichang2 = 0;

            double shichang3 = 0;

            //如果是周六周天，则所有时间都是有效时间

            if (startTime.DayOfWeek.ToString("d") == "0" || startTime.DayOfWeek.ToString("d") == "6")

            {

                ts = endTime - startTime;

                shichang1 = ts.TotalSeconds;

            }

            else

            {

                DateTime sys_startdate = Convert.ToDateTime(startTime.ToString("yyyy-MM-dd") + " " + "8:0:0");



                DateTime sys_enddate = Convert.ToDateTime(endTime.ToString("yyyy-MM-dd") + " " + "12:0:0");