截断. totalseconds很重要，因为它被定义为当前系统的值。以整个分数秒表示的timspan结构。

那DateTime的扩展呢?第二种方法可能更令人困惑，在存在属性扩展之前，它是值得的。

/// <summary>
/// Converts a given DateTime into a Unix timestamp
/// </summary>
/// <param name="value">Any DateTime</param>
/// <returns>The given DateTime in Unix timestamp format</returns>
public static int ToUnixTimestamp(this DateTime value)
{
    return (int)Math.Truncate((value.ToUniversalTime().Subtract(new DateTime(1970, 1, 1))).TotalSeconds);
}

/// <summary>
/// Gets a Unix timestamp representing the current moment
/// </summary>
/// <param name="ignored">Parameter ignored</param>
/// <returns>Now expressed as a Unix timestamp</returns>
public static int UnixTimestamp(this DateTime ignored)
{
    return (int)Math.Truncate((DateTime.UtcNow.Subtract(new DateTime(1970, 1, 1))).TotalSeconds);
}

下面是一个2-way扩展类，支持:

时区定位 输入/输出以秒或毫秒为单位。

在OP的例子中，用法是:

DateTime.Now.ToUnixtime();

or

DateTime.UtcNow.ToUnixtime();

尽管存在直接的答案，但我认为使用通用方法更好。 特别是因为它很可能是一个需要这样转换的项目，无论如何也需要这些扩展，所以最好对所有人使用相同的工具。

    public static class UnixtimeExtensions
    {
        public static readonly DateTime UNIXTIME_ZERO_POINT = new DateTime(1970, 1, 1, 0, 0,0, DateTimeKind.Utc);

        /// <summary>
        /// Converts a Unix timestamp (UTC timezone by definition) into a DateTime object
        /// </summary>
        /// <param name="value">An input of Unix timestamp in seconds or milliseconds format</param>
        /// <param name="localize">should output be localized or remain in UTC timezone?</param>
        /// <param name="isInMilliseconds">Is input in milliseconds or seconds?</param>
        /// <returns></returns>
        public static DateTime FromUnixtime(this long value, bool localize = false, bool isInMilliseconds = true)
        {
            DateTime result;

            if (isInMilliseconds)
            {
                result = UNIXTIME_ZERO_POINT.AddMilliseconds(value);
            }
            else
            {
                result = UNIXTIME_ZERO_POINT.AddSeconds(value);
            }

            if (localize)
                return result.ToLocalTime();
            else
                return result;
        }

        /// <summary>
        /// Converts a DateTime object into a Unix time stamp
        /// </summary>
        /// <param name="value">any DateTime object as input</param>
        /// <param name="isInMilliseconds">Should output be in milliseconds or seconds?</param>
        /// <returns></returns>
        public static long ToUnixtime(this DateTime value, bool isInMilliseconds = true)
        {
            if (isInMilliseconds)
            {
                return (long)value.ToUniversalTime().Subtract(UNIXTIME_ZERO_POINT).TotalMilliseconds;
            }
            else
            {
                return (long)value.ToUniversalTime().Subtract(UNIXTIME_ZERO_POINT).TotalSeconds;
            }
        }
    }

在c#中使用DateTime可以获得unix时间戳。UtcNow和减去1970年1月1日的纪元时间。

e.g.

Int32 unixTimestamp = (int)DateTime.UtcNow.Subtract(new DateTime(1970, 1, 1)).TotalSeconds;

DateTime。UtcNow可以替换为任何你想获取unix时间戳的DateTime对象。

还有一个字段DateTime。UnixEpoch，它在MSFT的文档中记录得非常少，但可以替代新的DateTime(1970,1,1)

我在挣扎了一段时间后使用了这个，它也迎合了时区偏移:

    public double Convert_DatTime_To_UNIXDATETIME(DateTime dt)
    {
        System.DateTime from_date = new DateTime(1970, 1, 1, 0, 0, 0, 0, System.DateTimeKind.Utc);
        double unix_time_since = dt.Subtract(from_date).TotalMilliseconds;

        TimeSpan ts_offset = TimeZoneInfo.Local.GetUtcOffset(DateTime.UtcNow);

        double offset = ts_offset.TotalMilliseconds;

        return unix_time_since - offset;
    }

这就是我用的。

 public class TimeStamp
    {
        public Int32 UnixTimeStampUTC()
        {
            Int32 unixTimeStamp;
            DateTime currentTime = DateTime.Now;
            DateTime zuluTime = currentTime.ToUniversalTime();
            DateTime unixEpoch = new DateTime(1970, 1, 1);
            unixTimeStamp = (Int32)(zuluTime.Subtract(unixEpoch)).TotalSeconds;
            return unixTimeStamp;
        }
}

这个解决方案对我的情况很有帮助:

   public class DateHelper {
     public static double DateTimeToUnixTimestamp(DateTime dateTime)
              {
                    return (TimeZoneInfo.ConvertTimeToUtc(dateTime) -
                             new DateTime(1970, 1, 1, 0, 0, 0, 0, System.DateTimeKind.Utc)).TotalSeconds;
              }
    }

在代码中使用helper:

double ret = DateHelper.DateTimeToUnixTimestamp(DateTime.Now)