`datetime` — 基本日期和时间类型 ¶

The datetime 模块提供用于操纵日期和时间的类。

While date and time arithmetic is supported, the focus of the implementation is on efficient attribute extraction for output formatting and manipulation.

另请参阅

模块 calendar
模块 time
包 dateutil

感知和单纯对象 ¶

Date and time objects may be categorized as “aware” or “naive” depending on whether or not they include timezone information.

With sufficient knowledge of applicable algorithmic and political time adjustments, such as time zone and daylight saving time information, an aware object can locate itself relative to other aware objects. An aware object represents a specific moment in time that is not open to interpretation. 1

A naive object does not contain enough information to unambiguously locate itself relative to other date/time objects. Whether a naive object represents Coordinated Universal Time (UTC), local time, or time in some other timezone is purely up to the program, just like it is up to the program whether a particular number represents metres, miles, or mass. Naive objects are easy to understand and to work with, at the cost of ignoring some aspects of reality.

For applications requiring aware objects, datetime and time objects have an optional time zone information attribute, tzinfo , that can be set to an instance of a subclass of the abstract tzinfo class. These tzinfo objects capture information about the offset from UTC time, the time zone name, and whether daylight saving time is in effect.

Only one concrete tzinfo 类， timezone class, is supplied by the datetime 模块。 timezone class can represent simple timezones with fixed offsets from UTC, such as UTC itself or North American EST and EDT timezones. Supporting timezones at deeper levels of detail is up to the application. The rules for time adjustment across the world are more political than rational, change frequently, and there is no standard suitable for every application aside from UTC.

常量 ¶

The datetime 模块导出下列常量：

datetime. MINYEAR ¶

datetime. MAXYEAR ¶

可用类型 ¶

class datetime. date

class datetime. time

class datetime. datetime

class datetime. timedelta

class datetime. tzinfo

class datetime. timezone

class datetime. timedelta ( days=0 , seconds=0 , microseconds=0 , milliseconds=0 , minutes=0 , hours=0 , weeks=0 ) ¶

If any argument is a float and there are fractional microseconds, the fractional microseconds left over from all arguments are combined and their sum is rounded to the nearest microsecond using round-half-to-even tiebreaker. If no argument is a float, the conversion and normalization processes are exact (no information is lost).

If the normalized value of days lies outside the indicated range, OverflowError 被引发。

Note that normalization of negative values may be surprising at first. For example:

>>> from datetime import timedelta
>>> d = timedelta(microseconds=-1)
>>> (d.days, d.seconds, d.microseconds)
(-1, 86399, 999999)

类属性：

timedelta. min ¶

timedelta. max ¶

timedelta. resolution ¶

属性	值
`days`	介于 -99999999999 和 999999999 (包括在内) 之间
`seconds`	介于 0 和 86399 (包括在内) 之间
`microseconds`	介于 0 和 999999 (包括在内) 之间

操作	结果
`t1 = t2 + t3`	Sum of t2 and t3 . Afterwards t1 - t2 == t3 and t1 - t3 == t2 are true. (1)
`t1 = t2 - t3`	Difference of t2 and t3 . Afterwards t1 == t2 - t3 and t2 == t1 + t3 are true. (1)(6)
`t1 = t2 * i or t1 = i * t2`	Delta multiplied by an integer. Afterwards t1 // i == t2 is true, provided `i != 0` .
	一般而言， t1 * i == t1 * (i-1) + t1 为 True。(1)
`t1 = t2 * f or t1 = f * t2`	Delta multiplied by a float. The result is rounded to the nearest multiple of timedelta.resolution using round-half-to-even.
`f = t2 / t3`	Division (3) of overall duration t2 by interval unit t3 。返回 `float` 对象。
`t1 = t2 / f or t1 = t2 / i`	Delta divided by a float or an int. The result is rounded to the nearest multiple of timedelta.resolution using round-half-to-even.
`t1 = t2 // i` or `t1 = t2 // t3`	The floor is computed and the remainder (if any) is thrown away. In the second case, an integer is returned. (3)
`t1 = t2 % t3`	The remainder is computed as a `timedelta` object. (3)
`q, r = divmod(t1, t2)`	Computes the quotient and the remainder: `q = t1 // t2` (3) and `r = t1 % t2` . q is an integer and r is a `timedelta` 对象。
`+t1`	返回 `timedelta` 对象具有相同值。(2)
`-t1`	相当于 `timedelta` (- t1.days , - t1.seconds , - t1.microseconds ), and to t1 * -1. (1)(4)
`abs(t)`	相当于 + t 当 `t.days >= 0` , and to - t 当 `t.days < 0` . (2)
`str(t)`	Returns a string in the form `[D day[s], ][H]H:MM:SS[.UUUUUU]` , where D is negative for negative `t` . (5)
`repr(t)`	Returns a string representation of the `timedelta` object as a constructor call with canonical attribute values.

对于所有其它比较 (譬如 < and > )，当 timedelta object is compared to an object of a different type, TypeError 被引发：

>>> delta2 > delta1
True
>>> delta2 > 5
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: '>' not supported between instances of 'datetime.timedelta' and 'int'

在布尔上下文， timedelta object is considered to be true if and only if it isn’t equal to timedelta(0) .

实例方法：

timedelta. total_seconds ( ) ¶

class datetime. date ( year , month , day ) ¶

classmethod date. today ( ) ¶

返回当前本地日期。

这相当于 date.fromtimestamp(time.time()) .

classmethod date. fromtimestamp ( timestamp ) ¶

Return the local date corresponding to the POSIX timestamp, such as is returned by time.time() .

This may raise OverflowError , if the timestamp is out of the range of values supported by the platform C localtime() function, and OSError on localtime() failure. It’s common for this to be restricted to years from 1970 through 2038. Note that on non-POSIX systems that include leap seconds in their notion of a timestamp, leap seconds are ignored by fromtimestamp() .

3.3 版改变：引发 OverflowError 而不是 ValueError if the timestamp is out of the range of values supported by the platform C localtime() 函数。引发 OSError 而不是 ValueError on localtime() 故障。

classmethod date. fromordinal ( ordinal ) ¶

Return the date corresponding to the proleptic Gregorian ordinal, where January 1 of year 1 has ordinal 1.

ValueError 被引发除非 1 <= ordinal <= date.max.toordinal() 。对于任何日期 d , date.fromordinal(d.toordinal()) == d .

classmethod date. fromisoformat ( date_string ) ¶
classmethod date. fromisocalendar ( year , week , day ) ¶
date. min ¶
date. max ¶
date. resolution ¶
date. year ¶
date. month ¶
date. day ¶
date. replace ( year=self.year , month=self.month , day=self.day ) ¶

操作	结果
`date2 = date1 + timedelta`	date2 is `timedelta.days` days removed from date1 . (1)
`date2 = date1 - timedelta`	计算 date2 这样 `date2 + timedelta == date1` . (2)
`timedelta = date1 - date2`	(3)
`date1 < date2`	date1 被认为小于 date2 当 date1 precedes date2 in time. (4)

date. __str__ ( ) ¶

classmethod datetime. utcnow ( ) ¶

classmethod datetime. fromtimestamp ( timestamp , tz=None ) ¶

classmethod datetime. utcfromtimestamp ( timestamp ) ¶

On the POSIX compliant platforms, it is equivalent to the following expression:

datetime(1970, 1, 1, tzinfo=timezone.utc) + timedelta(seconds=timestamp)

except the latter formula always supports the full years range: between MINYEAR and MAXYEAR 包括在内。

警告

Because naive datetime objects are treated by many datetime methods as local times, it is preferred to use aware datetimes to represent times in UTC. As such, the recommended way to create an object representing a specific timestamp in UTC is by calling datetime.fromtimestamp(timestamp, tz=timezone.utc) .

3.3 版改变：引发 OverflowError 而不是 ValueError if the timestamp is out of the range of values supported by the platform C gmtime() 函数。引发 OSError 而不是 ValueError on gmtime() 故障。

classmethod datetime. fromordinal ( ordinal ) ¶

classmethod datetime. combine ( date , time , tzinfo=self.tzinfo ) ¶

classmethod datetime. fromisoformat ( date_string ) ¶

where * can match any single character.

Caution

This does not support parsing arbitrary ISO 8601 strings - it is only intended as the inverse operation of datetime.isoformat() . A more full-featured ISO 8601 parser, dateutil.parser.isoparse is available in the third-party package dateutil .

范例：

>>> from datetime import datetime
>>> datetime.fromisoformat('2011-11-04')
datetime.datetime(2011, 11, 4, 0, 0)
>>> datetime.fromisoformat('2011-11-04T00:05:23')
datetime.datetime(2011, 11, 4, 0, 5, 23)
>>> datetime.fromisoformat('2011-11-04 00:05:23.283')
datetime.datetime(2011, 11, 4, 0, 5, 23, 283000)
>>> datetime.fromisoformat('2011-11-04 00:05:23.283+00:00')
datetime.datetime(2011, 11, 4, 0, 5, 23, 283000, tzinfo=datetime.timezone.utc)
>>> datetime.fromisoformat('2011-11-04T00:05:23+04:00')
datetime.datetime(2011, 11, 4, 0, 5, 23,
    tzinfo=datetime.timezone(datetime.timedelta(seconds=14400)))

3.7 版新增。

classmethod datetime. fromisocalendar ( year , week , day ) ¶

classmethod datetime. strptime ( date_string , format ) ¶

datetime. min ¶

datetime. max ¶

datetime. resolution ¶

datetime. year ¶

datetime. month ¶

datetime. day ¶

datetime. hour ¶

datetime. minute ¶

datetime. second ¶

datetime. microsecond ¶

datetime. tzinfo ¶

datetime. fold ¶

操作	结果
`datetime2 = datetime1 + timedelta`	(1)
`datetime2 = datetime1 - timedelta`	(2)
`timedelta = datetime1 - datetime2`	(3)
`datetime1 < datetime2`	比较 `datetime` to `datetime` . (4)

datetime. date ( ) ¶

datetime. time ( ) ¶

datetime. timetz ( ) ¶

datetime. replace ( year=self.year , month=self.month , day=self.day , hour=self.hour , minute=self.minute , second=self.second , microsecond=self.microsecond , tzinfo=self.tzinfo , * , fold=0 ) ¶

datetime. astimezone ( tz=None ) ¶

datetime. utcoffset ( ) ¶

datetime. dst ( ) ¶

datetime. tzname ( ) ¶

datetime. timetuple ( ) ¶

datetime. utctimetuple ( ) ¶

datetime. toordinal ( ) ¶

datetime. timestamp ( ) ¶

datetime. weekday ( ) ¶

datetime. isoweekday ( ) ¶

datetime. isocalendar ( ) ¶

datetime. isoformat ( sep='T' , timespec='auto' ) ¶

datetime. __str__ ( ) ¶

datetime. ctime ( ) ¶

datetime. strftime ( format ) ¶

datetime. __format__ ( format ) ¶

用法范例： `datetime` ¶

Examples of working with datetime 对象：

>>> from datetime import datetime, date, time, timezone
>>> # Using datetime.combine()
>>> d = date(2005, 7, 14)
>>> t = time(12, 30)
>>> datetime.combine(d, t)
datetime.datetime(2005, 7, 14, 12, 30)
>>> # Using datetime.now()
>>> datetime.now()
datetime.datetime(2007, 12, 6, 16, 29, 43, 79043)   # GMT +1
>>> datetime.now(timezone.utc)
datetime.datetime(2007, 12, 6, 15, 29, 43, 79060, tzinfo=datetime.timezone.utc)
>>> # Using datetime.strptime()
>>> dt = datetime.strptime("21/11/06 16:30", "%d/%m/%y %H:%M")
>>> dt
datetime.datetime(2006, 11, 21, 16, 30)
>>> # Using datetime.timetuple() to get tuple of all attributes
>>> tt = dt.timetuple()
>>> for it in tt:
...     print(it)
...
2006    # year
11      # month
21      # day
16      # hour
30      # minute
0       # second
1       # weekday (0 = Monday)
325     # number of days since 1st January
-1      # dst - method tzinfo.dst() returned None
>>> # Date in ISO format
>>> ic = dt.isocalendar()
>>> for it in ic:
...     print(it)
...
2006    # ISO year
47      # ISO week
2       # ISO weekday
>>> # Formatting a datetime
>>> dt.strftime("%A, %d. %B %Y %I:%M%p")
'Tuesday, 21. November 2006 04:30PM'
>>> 'The {1} is {0:%d}, the {2} is {0:%B}, the {3} is {0:%I:%M%p}.'.format(dt, "day", "month", "time")
'The day is 21, the month is November, the time is 04:30PM.'

The example below defines a tzinfo subclass capturing time zone information for Kabul, Afghanistan, which used +4 UTC until 1945 and then +4:30 UTC thereafter:

from datetime import timedelta, datetime, tzinfo, timezone
class KabulTz(tzinfo):
    # Kabul used +4 until 1945, when they moved to +4:30
    UTC_MOVE_DATE = datetime(1944, 12, 31, 20, tzinfo=timezone.utc)
    def utcoffset(self, dt):
        if dt.year < 1945:
            return timedelta(hours=4)
        elif (1945, 1, 1, 0, 0) <= dt.timetuple()[:5] < (1945, 1, 1, 0, 30):
            # An ambiguous ("imaginary") half-hour range representing
            # a 'fold' in time due to the shift from +4 to +4:30.
            # If dt falls in the imaginary range, use fold to decide how
            # to resolve. See PEP495.
            return timedelta(hours=4, minutes=(30 if dt.fold else 0))
        else:
            return timedelta(hours=4, minutes=30)
    def fromutc(self, dt):
        # Follow same validations as in datetime.tzinfo
        if not isinstance(dt, datetime):
            raise TypeError("fromutc() requires a datetime argument")
        if dt.tzinfo is not self:
            raise ValueError("dt.tzinfo is not self")
        # A custom implementation is required for fromutc as
        # the input to this function is a datetime with utc values
        # but with a tzinfo set to self.
        # See datetime.astimezone or fromtimestamp.
        if dt.replace(tzinfo=timezone.utc) >= self.UTC_MOVE_DATE:
            return dt + timedelta(hours=4, minutes=30)
        else:
            return dt + timedelta(hours=4)
    def dst(self, dt):
        # Kabul does not observe daylight saving time.
        return timedelta(0)
    def tzname(self, dt):
        if dt >= self.UTC_MOVE_DATE:
            return "+04:30"
        return "+04"

Usage of KabulTz from above:

>>> tz1 = KabulTz()
>>> # Datetime before the change
>>> dt1 = datetime(1900, 11, 21, 16, 30, tzinfo=tz1)
>>> print(dt1.utcoffset())
4:00:00
>>> # Datetime after the change
>>> dt2 = datetime(2006, 6, 14, 13, 0, tzinfo=tz1)
>>> print(dt2.utcoffset())
4:30:00
>>> # Convert datetime to another time zone
>>> dt3 = dt2.astimezone(timezone.utc)
>>> dt3
datetime.datetime(2006, 6, 14, 8, 30, tzinfo=datetime.timezone.utc)
>>> dt2
datetime.datetime(2006, 6, 14, 13, 0, tzinfo=KabulTz())
>>> dt2 == dt3
True

`time` 对象 ¶

A time object represents a (local) time of day, independent of any particular day, and subject to adjustment via a tzinfo 对象。

class datetime. time ( hour=0 , minute=0 , second=0 , microsecond=0 , tzinfo=None , * , fold=0 ) ¶

time. min ¶

time. max ¶

time. resolution ¶

time. hour ¶

time. minute ¶

time. second ¶

time. microsecond ¶

time. tzinfo ¶

time. fold ¶

classmethod time. fromisoformat ( time_string ) ¶

time. replace ( hour=self.hour , minute=self.minute , second=self.second , microsecond=self.microsecond , tzinfo=self.tzinfo , * , fold=0 ) ¶

time. isoformat ( timespec='auto' ) ¶

time. __str__ ( ) ¶

time. strftime ( format ) ¶

time. __format__ ( format ) ¶

time. utcoffset ( ) ¶

time. dst ( ) ¶

time. tzname ( ) ¶

用法范例： `time` ¶

Examples of working with a time 对象：

>>> from datetime import time, tzinfo, timedelta
>>> class TZ1(tzinfo):
...     def utcoffset(self, dt):
...         return timedelta(hours=1)
...     def dst(self, dt):
...         return timedelta(0)
...     def tzname(self,dt):
...         return "+01:00"
...     def  __repr__(self):
...         return f"{self.__class__.__name__}()"
...
>>> t = time(12, 10, 30, tzinfo=TZ1())
>>> t
datetime.time(12, 10, 30, tzinfo=TZ1())
>>> t.isoformat()
'12:10:30+01:00'
>>> t.dst()
datetime.timedelta(0)
>>> t.tzname()
'+01:00'
>>> t.strftime("%H:%M:%S %Z")
'12:10:30 +01:00'
>>> 'The {} is {:%H:%M}.'.format("time", t)
'The time is 12:10.'

`tzinfo` 对象 ¶

class datetime. tzinfo ¶

tzinfo. utcoffset ( dt ) ¶

tzinfo. dst ( dt ) ¶

tzinfo. tzname ( dt ) ¶

tzinfo. fromutc ( dt ) ¶

dateutil.tz
IANA timezone database

`timezone` 对象 ¶

The timezone 类是子类化的 tzinfo , each instance of which represents a timezone defined by a fixed offset from UTC.

Objects of this class cannot be used to represent timezone information in the locations where different offsets are used in different days of the year or where historical changes have been made to civil time.

class datetime. timezone ( offset , name=None ) ¶

timezone. utcoffset ( dt ) ¶

timezone. tzname ( dt ) ¶

timezone. dst ( dt ) ¶

timezone. fromutc ( dt ) ¶

timezone. utc ¶

`strftime()` and `strptime()` 行为 ¶

date , datetime ，和 time objects all support a strftime(format) method, to create a string representing the time under the control of an explicit format string.

Conversely, the datetime.strptime() class method creates a datetime object from a string representing a date and time and a corresponding format string.

The table below provides a high-level comparison of strftime() versus strptime() :

	`strftime`	`strptime`
用法	Convert object to a string according to a given format	Parse a string into a `datetime` object given a corresponding format
Type of method	Instance method	Class method
Method of	`date` ; `datetime` ; `time`	`datetime`
签名	`strftime(format)`	`strptime(date_string, format)`

`strftime()` and `strptime()` 格式代码 ¶

The following is a list of all the format codes that the 1989 C standard requires, and these work on all platforms with a standard C implementation.

指令	含义	范例	注意事项
`%a`	Weekday as locale’s abbreviated name.	Sun, Mon, …, Sat (en_US); So, Mo, …, Sa (de_DE)	(1)
`%A`	Weekday as locale’s full name.	Sunday, Monday, …, Saturday (en_US); Sonntag, Montag, …, Samstag (de_DE)	(1)
`%w`	Weekday as a decimal number, where 0 is Sunday and 6 is Saturday.	0, 1, …, 6
`%d`	Day of the month as a zero-padded decimal number.	01, 02, …, 31	(9)
`%b`	Month as locale’s abbreviated name.	Jan, Feb, …, Dec (en_US); Jan, Feb, …, Dez (de_DE)	(1)
`%B`	Month as locale’s full name.	January, February, …, December (en_US); Januar, Februar, …, Dezember (de_DE)	(1)
`%m`	Month as a zero-padded decimal number.	01, 02, …, 12	(9)
`%y`	Year without century as a zero-padded decimal number.	00, 01, …, 99	(9)
`%Y`	带有世纪的年份如十进制数。	0001, 0002, …, 2013, 2014, …, 9998, 9999	(2)
`%H`	Hour (24-hour clock) as a zero-padded decimal number.	00, 01, …, 23	(9)
`%I`	Hour (12-hour clock) as a zero-padded decimal number.	01, 02, …, 12	(9)
`%p`	区域设置的 AM 或 PM 等价。	AM, PM (en_US); am, pm (de_DE)	(1), (3)
`%M`	Minute as a zero-padded decimal number.	00, 01, …, 59	(9)
`%S`	Second as a zero-padded decimal number.	00, 01, …, 59	(4), (9)
`%f`	Microsecond as a decimal number, zero-padded on the left.	000000, 000001, …, 999999	(5)
`%z`	UTC offset in the form `±HHMM[SS[.ffffff]]` (empty string if the object is naive).	(empty), +0000, -0400, +1030, +063415, -030712.345216	(6)
`%Z`	Time zone name (empty string if the object is naive).	(empty), UTC, EST, CST
`%j`	Day of the year as a zero-padded decimal number.	001, 002, …, 366	(9)
`%U`	Week number of the year (Sunday as the first day of the week) as a zero padded decimal number. All days in a new year preceding the first Sunday are considered to be in week 0.	00, 01, …, 53	(7), (9)
`%W`	Week number of the year (Monday as the first day of the week) as a decimal number. All days in a new year preceding the first Monday are considered to be in week 0.	00, 01, …, 53	(7), (9)
`%c`	区域设置的适当日期和时间表示。	Tue Aug 16 21:30:00 1988 (en_US); Di 16 Aug 21:30:00 1988 (de_DE)	(1)
`%x`	区域设置的适当日期表示。	08/16/88 (None); 08/16/1988 (en_US); 16.08.1988 (de_DE)	(1)
`%X`	区域设置的适当时间表示。	21:30:00 (en_US); 21:30:00 (de_DE)	(1)
`%%`	文字 `'%'` 字符。	%

Several additional directives not required by the C89 standard are included for convenience. These parameters all correspond to ISO 8601 date values.

指令	含义	范例	注意事项
`%G`	ISO 8601 year with century representing the year that contains the greater part of the ISO week ( `%V` ).	0001, 0002, …, 2013, 2014, …, 9998, 9999	(8)
`%u`	ISO 8601 weekday as a decimal number where 1 is Monday.	1, 2, …, 7
`%V`	ISO 8601 week as a decimal number with Monday as the first day of the week. Week 01 is the week containing Jan 4.	01, 02, …, 53	(8), (9)

These may not be available on all platforms when used with the strftime() method. The ISO 8601 year and ISO 8601 week directives are not interchangeable with the year and week number directives above. Calling strptime() with incomplete or ambiguous ISO 8601 directives will raise a ValueError .

The full set of format codes supported varies across platforms, because Python calls the platform C library’s strftime() function, and platform variations are common. To see the full set of format codes supported on your platform, consult the strftime(3) 文档编制。

3.6 版新增： %G , %u and %V 被添加。

技术细节 ¶

Broadly speaking, d.strftime(fmt) acts like the time 模块的 time.strftime(fmt, d.timetuple()) although not all objects support a timetuple() 方法。

对于 datetime.strptime() class method, the default value is 1900-01-01T00:00:00.000 : any components not specified in the format string will be pulled from the default value. 4

使用 datetime.strptime(date_string, format) 相当于：

datetime(*(time.strptime(date_string, format)[0:6]))

except when the format includes sub-second components or timezone offset information, which are supported in datetime.strptime but are discarded by time.strptime .

For time objects, the format codes for year, month, and day should not be used, as time objects have no such values. If they’re used anyway, 1900 is substituted for the year, and 1 for the month and day.

For date objects, the format codes for hours, minutes, seconds, and microseconds should not be used, as date objects have no such values. If they’re used anyway, 0 is substituted for them.

For the same reason, handling of format strings containing Unicode code points that can’t be represented in the charset of the current locale is also platform-dependent. On some platforms such code points are preserved intact in the output, while on others strftime 可能引发 UnicodeError or return an empty string instead.

注意事项：

Because the format depends on the current locale, care should be taken when making assumptions about the output value. Field orderings will vary (for example, “month/day/year” versus “day/month/year”), and the output may contain Unicode characters encoded using the locale’s default encoding (for example, if the current locale is ja_JP , the default encoding could be any one of eucJP , SJIS ，或 utf-8 ；使用 locale.getlocale() to determine the current locale’s encoding).
The strptime() method can parse years in the full [1, 9999] range, but years < 1000 must be zero-filled to 4-digit width.

3.2 版改变： In previous versions, strftime() method was restricted to years >= 1900.

3.3 版改变： In version 3.2, strftime() method was restricted to years >= 1000.
当用于 strptime() method, the %p directive only affects the output hour field if the %I directive is used to parse the hour.
不像 time module, the datetime module does not support leap seconds.
当用于 strptime() method, the %f directive accepts from one to six digits and zero pads on the right. %f is an extension to the set of format characters in the C standard (but implemented separately in datetime objects, and therefore always available).
For a naive object, the %z and %Z format codes are replaced by empty strings.

For an aware object:

%z

utcoffset() is transformed into a string of the form ±HHMM[SS[.ffffff]] ，其中 HH is a 2-digit string giving the number of UTC offset hours, MM is a 2-digit string giving the number of UTC offset minutes, SS is a 2-digit string giving the number of UTC offset seconds and ffffff is a 6-digit string giving the number of UTC offset microseconds. The ffffff part is omitted when the offset is a whole number of seconds and both the ffffff 和 SS part is omitted when the offset is a whole number of minutes. For example, if utcoffset() 返回 timedelta(hours=-3, minutes=-30) , %z is replaced with the string '-0330' .

3.7 版改变： The UTC offset is not restricted to a whole number of minutes.

3.7 版改变：当 %z directive is provided to the strptime() method, the UTC offsets can have a colon as a separator between hours, minutes and seconds. For example, '+01:00:00' will be parsed as an offset of one hour. In addition, providing 'Z' is identical to '+00:00' .

%Z

若 tzname() 返回 None , %Z is replaced by an empty string. Otherwise %Z is replaced by the returned value, which must be a string.

3.2 版改变：当 %z directive is provided to the strptime() method, an aware datetime object will be produced. The tzinfo of the result will be set to a timezone 实例。
当用于 strptime() 方法， %U and %W are only used in calculations when the day of the week and the calendar year ( %Y ) are specified.
类似于 %U and %W , %V is only used in calculations when the day of the week and the ISO year ( %G ) are specified in a strptime() format string. Also note that %G and %Y are not interchangeable.
当用于 strptime() method, the leading zero is optional for formats %d , %m , %H , %I , %M , %S , %J , %U , %W ，和 %V . Format %y does require a leading zero.

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`datetime` — 基本日期和时间类型 ¶

感知和单纯对象 ¶

常量 ¶

可用类型 ¶

公共特性 ¶

确定是感知还是单纯对象 ¶

`timedelta` 对象 ¶

用法范例： `timedelta` ¶

`date` 对象 ¶

用法范例： `date` ¶

`datetime` 对象 ¶

用法范例： `datetime` ¶

`time` 对象 ¶

用法范例： `time` ¶

`tzinfo` 对象 ¶

`timezone` 对象 ¶

`strftime()` and `strptime()` 行为 ¶

`strftime()` and `strptime()` 格式代码 ¶

技术细节 ¶

内容表

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datetime — 基本日期和时间类型 ¶

感知和单纯对象 ¶

常量 ¶

可用类型 ¶

公共特性 ¶

确定是感知还是单纯对象 ¶

timedelta 对象 ¶

用法范例： timedelta ¶

date 对象 ¶

用法范例： date ¶

datetime 对象 ¶

用法范例： datetime ¶

time 对象 ¶

用法范例： time ¶

tzinfo 对象 ¶

timezone 对象 ¶

strftime() and strptime() 行为 ¶

strftime() and strptime() 格式代码 ¶

技术细节 ¶

内容表

上一话题

下一话题

本页

快速搜索

`datetime` — 基本日期和时间类型 ¶

`timedelta` 对象 ¶

用法范例： `timedelta` ¶

`date` 对象 ¶

用法范例： `date` ¶

`datetime` 对象 ¶

用法范例： `datetime` ¶

`time` 对象 ¶

用法范例： `time` ¶

`tzinfo` 对象 ¶

`timezone` 对象 ¶

`strftime()` and `strptime()` 行为 ¶

`strftime()` and `strptime()` 格式代码 ¶