asp.net时间比较

        public static int DateDiffDay(DateTime DateTimeOld, DateTime DateTimeNew)
        {
            TimeSpan ts1 = new TimeSpan(DateTimeOld.Ticks);
            TimeSpan ts2 = new TimeSpan(DateTimeNew.Ticks);
            TimeSpan ts = ts1.Subtract(ts2).Duration();
            int day = ts.Days;
            if (day < -3)
                return -1;
            else if (day == 0)
                return 1;
            else return 0;
        }