计算两个时间段相差天数

  /// <summary>
        /// 计算两个时间段相差天数
        /// </summary>
        /// <param name="begintime">开始时间（不带时分秒）</param>
        /// <param name="endtime">结束时间（不带时分秒）</param>
        /// <returns></returns>
        public static int GetTimeDifference(DateTime begintime, DateTime endtime)
        {
            if (begintime > endtime) { return 0; }
            TimeSpan ts1 = new TimeSpan(begintime.Ticks);
            TimeSpan ts2 = new TimeSpan(endtime.Ticks);
            TimeSpan ts = ts1.Subtract(ts2).Duration();
            return ts.Days;
        }