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。
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
我在dateutil(在SO网站上被广泛推荐用于其他相关问题)方面运气不错:
from datetime import *
from dateutil import *
from dateutil.tz import *
# METHOD 1: Hardcode zones:
utc_zone = tz.gettz('UTC')
local_zone = tz.gettz('America/Chicago')
# METHOD 2: Auto-detect zones:
utc_zone = tz.tzutc()
local_zone = tz.tzlocal()
# Convert time string to datetime
local_time = datetime.strptime("2008-09-17 14:02:00", '%Y-%m-%d %H:%M:%S')
# Tell the datetime object that it's in local time zone since
# datetime objects are 'naive' by default
local_time = local_time.replace(tzinfo=local_zone)
# Convert time to UTC
utc_time = local_time.astimezone(utc_zone)
# Generate UTC time string
utc_string = utc_time.strftime('%Y-%m-%d %H:%M:%S')
(代码是从这个答案派生的,将UTC日期时间字符串转换为本地日期时间)