private static int dateDiff(DateTime dtStart, DateTime dtEnd)        {            TimeSpan tsStart = new TimeSpan(dtStart.Ticks);            TimeSpan tsEnd = new TimeSpan(dtEnd.Ticks);            TimeSpan ts = tsEnd.Subtract(tsStart).Duration();            int dateDiffSecond = ts.Days * 24 * 60 * 60 + ts.Hours * 60 * 60 + ts.Minutes * 60 + ts.Seconds;            //两个时间的秒差            return dateDiffSecond;        }