如何将本地时间的datetime字符串转换为UTC时间的字符串?

我确信我以前做过这个,但找不到它,所以希望将来能帮助我(和其他人)做到这一点。

澄清:例如,如果我的本地时区(+10)是2008-09-17 14:02:00,我希望生成一个具有等效UTC时间的字符串:2008-09-17 04:02:00。

此外,从http://lucumr.pocoo.org/2011/7/15/eppur-si-muove/请注意,一般来说,这是不可能的,因为DST和其他问题没有从本地时间到UTC时间的唯一转换。


当前回答

怎么样——

time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime(seconds))

如果seconds为None,则将本地时间转换为UTC时间,否则将传入的时间转换为UTC时间。

其他回答

首先,将字符串解析为简单的datetime对象。这是datetime的一个实例。没有附加时区信息的日期时间。请参阅其文档。

使用pytz模块,该模块提供了时区+ UTC的完整列表。找出本地时区是什么,从它构造一个timezone对象,并操作它并将其附加到naive datetime。

最后,使用datetime.astimezone()方法将datetime转换为UTC。

源代码,使用本地时区“America/Los_Angeles”,用于字符串“2001-2-3 10:11:12”:

from datetime import datetime   
import pytz

local = pytz.timezone("America/Los_Angeles")
naive = datetime.strptime("2001-2-3 10:11:12", "%Y-%m-%d %H:%M:%S")
local_dt = local.localize(naive, is_dst=None)
utc_dt = local_dt.astimezone(pytz.utc)

从那里,你可以使用strftime()方法来格式化UTC日期时间:

utc_dt.strftime("%Y-%m-%d %H:%M:%S")
import time

import datetime

def Local2UTC(LocalTime):

    EpochSecond = time.mktime(LocalTime.timetuple())
    utcTime = datetime.datetime.utcfromtimestamp(EpochSecond)

    return utcTime

>>> LocalTime = datetime.datetime.now()

>>> UTCTime = Local2UTC(LocalTime)

>>> LocalTime.ctime()

'Thu Feb  3 22:33:46 2011'

>>> UTCTime.ctime()

'Fri Feb  4 05:33:46 2011'

你可以用:

>>> from time import strftime, gmtime, localtime
>>> strftime('%H:%M:%S', gmtime()) #UTC time
>>> strftime('%H:%M:%S', localtime()) # localtime

下面是一些常见的Python时间转换的总结。

有些方法以秒为单位,用(s)标记。可以使用显式公式,如ts = (d - epoch) / unit代替(感谢jfs)。

struct_time (UTC) → POSIX (s):calendar.timegm(struct_time) Naïve datetime (local) → POSIX (s):calendar.timegm(stz.localize(dt, is_dst=None).utctimetuple())(exception during DST transitions, see comment from jfs) Naïve datetime (UTC) → POSIX (s):calendar.timegm(dt.utctimetuple()) Aware datetime → POSIX (s):calendar.timegm(dt.utctimetuple()) POSIX → struct_time (UTC, s):time.gmtime(t)(see comment from jfs) Naïve datetime (local) → struct_time (UTC, s):stz.localize(dt, is_dst=None).utctimetuple()(exception during DST transitions, see comment from jfs) Naïve datetime (UTC) → struct_time (UTC, s):dt.utctimetuple() Aware datetime → struct_time (UTC, s):dt.utctimetuple() POSIX → Naïve datetime (local):datetime.fromtimestamp(t, None)(may fail in certain conditions, see comment from jfs below) struct_time (UTC) → Naïve datetime (local, s):datetime.datetime(struct_time[:6], tzinfo=UTC).astimezone(tz).replace(tzinfo=None)(can't represent leap seconds, see comment from jfs) Naïve datetime (UTC) → Naïve datetime (local):dt.replace(tzinfo=UTC).astimezone(tz).replace(tzinfo=None) Aware datetime → Naïve datetime (local):dt.astimezone(tz).replace(tzinfo=None) POSIX → Naïve datetime (UTC):datetime.utcfromtimestamp(t) struct_time (UTC) → Naïve datetime (UTC, s):datetime.datetime(*struct_time[:6])(can't represent leap seconds, see comment from jfs) Naïve datetime (local) → Naïve datetime (UTC):stz.localize(dt, is_dst=None).astimezone(UTC).replace(tzinfo=None)(exception during DST transitions, see comment from jfs) Aware datetime → Naïve datetime (UTC):dt.astimezone(UTC).replace(tzinfo=None) POSIX → Aware datetime:datetime.fromtimestamp(t, tz)(may fail for non-pytz timezones) struct_time (UTC) → Aware datetime (s):datetime.datetime(struct_time[:6], tzinfo=UTC).astimezone(tz)(can't represent leap seconds, see comment from jfs) Naïve datetime (local) → Aware datetime:stz.localize(dt, is_dst=None)(exception during DST transitions, see comment from jfs) Naïve datetime (UTC) → Aware datetime:dt.replace(tzinfo=UTC)

来源:taaviburns.ca

如果你喜欢datetime.datetime:

dt = datetime.strptime("2008-09-17 14:04:00","%Y-%m-%d %H:%M:%S")
utc_struct_time = time.gmtime(time.mktime(dt.timetuple()))
utc_dt = datetime.fromtimestamp(time.mktime(utc_struct_time))
print dt.strftime("%Y-%m-%d %H:%M:%S")