DateTime to time_t在c ++端产生Hour：2

The below code snippet convert DateTime to time_t in c#. When in C++, i convert it back using localtime_s I get tm_hour = 2, why?

下面的代码片段将dateTime转换为c#中的time_t。在C ++中,我使用localtime_s将其转换回来我得到tm_hour = 2,为什么?

I convert: DateTimeUtils.Secs(DateTime.Parse("2015-05-01"))

public static Int64 Secs(DateTime dt)
    {
      var delta = dt - new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
      return Convert.ToInt64(delta.TotalSeconds);
    }

time_t DropTimeFromDate(time_t time)
    {
        struct tm timeInfo;
        localtime_s(&timeInfo, &time);              

        timeInfo.tm_hour = 0;
        timeInfo.tm_min = 0;
        timeInfo.tm_sec = 0;        

        return mktime(&timeInfo);               
    }

Should I somehow fix the c# conversion?

我应该以某种方式修复c#转换?

1 个解决方案

#1

I'm in the UK, presently UTC+1:00 (British Summer Time), running your code I get a tm_hour of 1 rather than 2 which I can only guess is due to us being in different timezones (UTC+1 isn't always UTC+1, timezones are just a headache in general)

我在英国,目前UTC + 1:00(英国夏令时间),运行你的代码我得到1而不是2的tm_hour我只能猜测是因为我们在不同的时区(UTC + 1 isn'总是UTC + 1,时区只是一个令人头疼的问题)

Either way the problem down to the C++ or C code you're using to convert back to time_t - the C# code is fine

无论哪种方式问题都归结为你用来转换回time_t的C ++或C代码 - C#代码很好

if you change localtime_s(&timeInfo, time) to gmtime_s(&timeInfo, time)

如果你将localtime_s(&timeInfo,time)更改为gmtime_s(&timeInfo,time)

you should have better luck, the latter ignores the current timezone and just treats the value as a raw UTC time which is best to work with if you can

你应该有更好的运气,后者忽略当前的时区,只是将值视为原始UTC时间,如果可以,最好使用

#1