系统中DateTimeOffset有一个tounixtimemillisecseconds

你可以为DateTime写类似的方法:

public static long ToUnixTimeSeconds(this DateTime value)
{
    return value.Ticks / 10000000L - 62135596800L;
}

10000000L—将刻度转换为秒

62135596800L -将01.01.01转换为01.01.1978

Utc和泄漏没有问题

如果你有一个长时间的UTC时间戳，还有一个更快的快捷方式。

        /// <summary>
        /// Convert Ticks to Unix Timestamp
        /// </summary>
        /// <param name="time"></param>
        /// <returns></returns>
        public static long ToUnixTimestamp(long time)
        {
            return (time - 621355968000000000) / TimeSpan.TicksPerMillisecond;
        }

使用。net 6.0，使用long避免2038问题:

DateTime。UtcNow到UnixTime:

long seconds = (long)DateTime.UtcNow.Subtract(DateTime.UnixEpoch).TotalSeconds;

(seconds是一个长值，将包含自01/01/1970或UnixTime以来的秒数)

UnixTime到DateTime。UtcNow:

DateTime timestamp = DateTime.UnixEpoch.AddSeconds(seconds);

小提琴:https://dotnetfiddle.net/xNhO6q

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)

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;
            }
        }
    }