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
在python3:
PIP安装python-dateutil
from dateutil.parser import tz
mydt.astimezone(tz.gettz('UTC')).replace(tzinfo=None)
其他回答
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
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'
下面是Python3.9中本地zoneinfo模块的示例:
from datetime import datetime
from zoneinfo import ZoneInfo
# Get timezone we're trying to convert from
local_tz = ZoneInfo("America/New_York")
# UTC timezone
utc_tz = ZoneInfo("UTC")
dt = datetime.strptime("2021-09-20 17:20:00","%Y-%m-%d %H:%M:%S")
dt = dt.replace(tzinfo=local_tz)
dt_utc = dt.astimezone(utc_tz)
print(dt.strftime("%Y-%m-%d %H:%M:%S"))
print(dt_utc.strftime("%Y-%m-%d %H:%M:%S"))
在转换的时区不反映系统本地时区的情况下，这可能比仅使用dt.astimezone()更可取。不必依赖外部库也很好。
注意:这可能在Windows系统上不起作用，因为zoneinfo依赖于可能不存在的IANA数据库。tzdata包可以作为解决方案安装。它是第一方包，但不在标准库中。
def local_to_utc(t):
secs = time.mktime(t)
return time.gmtime(secs)
def utc_to_local(t):
secs = calendar.timegm(t)
return time.localtime(secs)
来源:http://feihonghsu.blogspot.com/2008/02/converting-from-local-time-to-utc.html
来自bd808的示例用法:如果您的源是一个datetime。Datetime对象t，调用as:
local_to_utc(t.timetuple())
你可以用:
>>> from time import strftime, gmtime, localtime
>>> strftime('%H:%M:%S', gmtime()) #UTC time
>>> strftime('%H:%M:%S', localtime()) # localtime
