计算两个日期相隔的天数

        /// <summary>
        /// 计算两个日期相隔的天数
        /// </summary>
        /// <param name="startdate">开始日期</param>
        /// <param name="enddate">结束日期</param>
        /// <returns></returns>
        public static int GetDayInterval(DateTime startdate, DateTime enddate)
        {
            TimeSpan sts = new TimeSpan(startdate.Ticks);
            TimeSpan ets = new TimeSpan(enddate.Ticks);
            int days = ets.Subtract(sts).Duration().Days;
            return days;
        }

}