你也可以使用Ticks。我正在为Windows Mobile编写代码，所以没有完整的方法集。我无法使用TotalSeconds。

long epochTicks = new DateTime(1970, 1, 1).Ticks;
long unixTime = ((DateTime.UtcNow.Ticks - epochTicks) / TimeSpan.TicksPerSecond);

or

TimeSpan epochTicks = new TimeSpan(new DateTime(1970, 1, 1).Ticks);
TimeSpan unixTicks = new TimeSpan(DateTime.UtcNow.Ticks) - epochTicks;
double unixTime = unixTicks.TotalSeconds;

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);
}

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)

我已经拼接了这个实用方法的最优雅的方法:

public static class Ux {
    public static decimal ToUnixTimestampSecs(this DateTime date) => ToUnixTimestampTicks(date) / (decimal) TimeSpan.TicksPerSecond;
    public static long ToUnixTimestampTicks(this DateTime date) => date.ToUniversalTime().Ticks - UnixEpochTicks;
    private static readonly long UnixEpochTicks = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc).Ticks;
}

这是我所使用的:

public long UnixTimeNow()
{
    var timeSpan = (DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0));
    return (long)timeSpan.TotalSeconds;
}

请记住，此方法将返回协调世界时(UTC)的时间。

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;
    }