在 Python 中解析时间字符串

我有一个日期时间字符串,我不知道如何在 Python 中解析它。

字符串是这样的:

Tue May 08 15:14:45 +0800 2012

我尽力了

datetime.strptime("Tue May 08 15:14:45 +0800 2012","%a %b %d %H:%M:%S %z %Y")

但巨蟒加注了

'z' is a bad directive in format '%a %b %d %H:%M:%S %z %Y'

根据 Python 文档:

形式为 + HHMM 或-HHMM (如果对象是初始的,则为空字符串)的 UTC 偏移量。

解析这个时间字符串的正确格式是什么?

146348 次浏览
In [117]: datetime.datetime.strptime?
Type:           builtin_function_or_method
Base Class:     <type 'builtin_function_or_method'>
String Form:    <built-in method strptime of type object at 0x9a2520>
Namespace:      Interactive
Docstring:
string, format -> new datetime parsed from a string (like time.strptime()).

datetime.datetime.strptime has problems with timezone parsing. Have a look at the dateutil package:

>>> from dateutil import parser
>>> parser.parse("Tue May 08 15:14:45 +0800 2012")
datetime.datetime(2012, 5, 8, 15, 14, 45, tzinfo=tzoffset(None, 28800))

Your best bet is to have a look at strptime()

Something along the lines of

>>> from datetime import datetime
>>> date_str = 'Tue May 08 15:14:45 +0800 2012'
>>> date = datetime.strptime(date_str, '%a %B %d %H:%M:%S +0800 %Y')
>>> date
datetime.datetime(2012, 5, 8, 15, 14, 45)

Im not sure how to do the +0800 timezone unfortunately, maybe someone else can help out with that.

The formatting strings can be found at http://docs.python.org/library/time.html#time.strftime and are the same for formatting the string for printing.

Hope that helps

Mark

PS, Your best bet for timezones in installing pytz from pypi. ( http://pytz.sourceforge.net/ ) in fact I think pytz has a great datetime parsing method if i remember correctly. The standard lib is a little thin on the ground with timezone functionality.

It has discussed many times in SO. In short, "%z" is not supported because platform not support it. My solution is a new one, just skip the time zone.:

    datetime.datetime.strptime(re.sub(r"[+-]([0-9])+", "", "Tue May 08 15:14:45 +0800 2012"),"%a %b %d %H:%M:%S %Y")

Here's a stdlib solution that supports a variable utc offset in the input time string:

>>> from email.utils import parsedate_tz, mktime_tz
>>> from datetime import datetime, timedelta
>>> timestamp = mktime_tz(parsedate_tz('Tue May 08 15:14:45 +0800 2012'))
>>> utc_time = datetime(1970, 1, 1) + timedelta(seconds=timestamp)
>>> utc_time
datetime.datetime(2012, 5, 8, 7, 14, 45)