下面介绍C#生成日期与时间的方法

主要涉及到2个类，DateTime 和 TimeSpan 

 　　　　　　//获取当前时间
            DateTime now = DateTime.Now;
            int year = now.Year;
            int month = now.Month;
            int day = now.Day;
            int hour = now.Hour;

            //DateTime 转换 string
            string dateTime1 = now.ToString("yyyy-MM-dd HH:mm:ss");

            //string 转换 DateTime
            DateTime dateTime2 = DateTime.ParseExact("2021/10/30 18:02:00", "yyyy/MM/dd HH:mm:ss", CultureInfo.InvariantCulture);

            //时间戳生成
            TimeSpan universal = DateTime.Now.ToUniversalTime().Subtract(new DateTime(1970, 1, 1));
            //秒级
            long seconds = (long)universal.TotalSeconds;
            //毫秒级
            long milli = (long)universal.TotalMilliseconds;