pytz 本地化 vs 日期时间替换

问题描述

我在使用 pytz 的 .localize() 函数时遇到了一些奇怪的问题.有时它不会对本地化的日期时间进行调整:

.localize 行为:

>>>茨<DstTzInfo 'Africa/Abidjan' LMT-1 天，23:44:00 STD>>>>ddatetime.datetime(2009, 9, 2, 14, 45, 42, 91421)>>>tz.localize(d)datetime.datetime(2009, 9, 2, 14, 45, 42, 91421,tzinfo=)>>>tz.normalize(tz.localize(d))datetime.datetime(2009, 9, 2, 14, 45, 42, 91421,tzinfo=)

如您所见，本地化/规范化操作并未改变时间.但是，如果使用 .replace:

>>>d.replace(tzinfo=tz)datetime.datetime(2009, 9, 2, 14, 45, 42, 91421,tzinfo=<DstTzInfo '非洲/阿比让' LMT-1 天，23:44:00 STD>)>>>tz.normalize(d.replace(tzinfo=tz))datetime.datetime(2009, 9, 2, 15, 1, 42, 91421,tzinfo=)

这似乎对日期时间进行了调整.

问题是 - 哪个是正确的，为什么别人是错的?

解决方案

localize 只是假设您传递的原始日期时间是正确的"(除了不知道时区！)等等只设置时区，没有其他调整.

您可以(并且建议...)在 UTC 内部工作(而不是使用幼稚的日期时间)并在需要以本地化方式执行日期时间的 I/O 时使用 replace(normalize 将处理 DST 等).

I'm having some weird issues with pytz's .localize() function. Sometimes it wouldn't make adjustments to the localized datetime:

.localize behaviour:

>>> tz
<DstTzInfo 'Africa/Abidjan' LMT-1 day, 23:44:00 STD>
>>> d
datetime.datetime(2009, 9, 2, 14, 45, 42, 91421)

>>> tz.localize(d)
datetime.datetime(2009, 9, 2, 14, 45, 42, 91421,
                  tzinfo=<DstTzInfo 'Africa/Abidjan' GMT0:00:00 STD>)
>>> tz.normalize(tz.localize(d))
datetime.datetime(2009, 9, 2, 14, 45, 42, 91421,
                  tzinfo=<DstTzInfo 'Africa/Abidjan' GMT0:00:00 STD>)

As you can see, time has not been changed as a result of localize/normalize operations.However, if .replace is used:

>>> d.replace(tzinfo=tz)
datetime.datetime(2009, 9, 2, 14, 45, 42, 91421,
                  tzinfo=<DstTzInfo 'Africa/Abidjan' LMT-1 day, 23:44:00 STD>)
>>> tz.normalize(d.replace(tzinfo=tz))
datetime.datetime(2009, 9, 2, 15, 1, 42, 91421,
                  tzinfo=<DstTzInfo 'Africa/Abidjan' GMT0:00:00 STD>)

Which seems to make adjustments into datetime.

Question is - which is correct and why other's wrong?

解决方案

localize just assumes that the naive datetime you pass it is "right" (except for not knowing about the timezone!) and so just sets the timezone, no other adjustments.

You can (and it's advisable...) internally work in UTC (rather than with naive datetimes) and use replace when you need to perform I/O of datetimes in a localized way (normalize will handle DST and the like).

这篇关于pytz 本地化 vs 日期时间替换的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！