Python字符串转换为日期时间– strptime

We can convert a string to datetime using strptime() function. This function is available in datetime and time modules to parse a string to datetime and time objects respectively.

我们可以使用strptime()函数将字符串转换为datetime。 datetimetime模块中提供了此功能,可分别将字符串解析为datetime和time对象。

Python strptime() (Python strptime())

Python strptime() is a class method in datetime class. Its syntax is:

Python strptime()是datetime类中的类方法。 其语法为:

datetime.strptime(date_string, format)

Both the arguments are mandatory and should be string. This function is exactly opposite of strftime() function, which converts datetime object to a string.

这两个参数都是强制性的,应为字符串。 此函数与strftime()函数完全相反,该函数将datetime对象转换为字符串。

We have the similar function available in time module too, where its syntax is:


time.strptime(time_string[, format])

Here the function returns struct_time object. If format string is not provided, it defaults to “%a %b %d %H:%M:%S %Y” which matches the formatting returned by ctime() function.

在这里,该函数返回struct_time对象。 如果未提供格式字符串,则默认为“%a%b%d%H:%M:%S%Y”,它与ctime()函数返回的格式匹配。

If the input string cannot be parsed according to the provided format, then ValueError is raised. The exception message provides clear details about the issue in parsing.

如果无法根据提供的格式解析输入字符串,则引发ValueError 。 异常消息提供了有关解析中问题的清晰详细信息。


Python strptime()格式指令 (Python strptime() format directives)

Following table contains most of the commonly used format directives.


DirectiveDescriptionExample Output
%a Weekday as locale’s abbreviated name. Sun, Mon, …, Sat (en_US)
So, Mo, …, Sa (de_DE)
%A Weekday as locale’s full name. Sunday, Monday, …, Saturday (en_US)
Sonntag, Montag, …, Samstag (de_DE)
%w Weekday as a decimal number, where 0 is Sunday and 6 is Saturday. 0, 1, 2, 3, 4, 5, 6
%d Day of the month as a zero-padded decimal number. 01, 02, …, 31
%b Month as locale’s abbreviated name. Jan, Feb, …, Dec (en_US)
Jan, Feb, …, Dez (de_DE)
%B Month as locale’s full name. January, February, …, December (en_US)
Januar, Februar, …, Dezember (de_DE)
%m Month as a zero-padded decimal number. 01, 02 … 12
%y Year without century as a zero-padded decimal number. 01, 02, … 99
%Y Year with century as a decimal number. 0001, 0002, … , 9999
%H Hour (24-hour clock) as a zero-padded decimal number. 01, 02, … , 23
%I Hour (12-hour clock) as a zero-padded decimal number. 01, 02, … , 12
%p Locale’s equivalent of either AM or PM. AM, PM (en_US)
am, pm (de_DE)
%M Minute as a zero-padded decimal number. 01, 02, … , 59
%S Second as a zero-padded decimal number. 01, 02, … , 59
%f Microsecond as a decimal number, zero-padded on the left. 000000, 000001, …, 999999
Not applicable with time module.
%z UTC offset in the form ±HHMM[SS] (empty string if the object is naive). (empty), +0000, -0400, +1030
%Z Time zone name (empty string if the object is naive). (empty), UTC, IST, CST
%j Day of the year as a zero-padded decimal number. 001, 002, …, 366
%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
%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
%c Locale’s appropriate date and time representation. Tue Aug 16 21:30:00 1988 (en_US)
Di 16 Aug 21:30:00 1988 (de_DE)
%x Locale’s appropriate date representation. 08/16/88 (None)
08/16/1988 (en_US)
16.08.1988 (de_DE)
%X Locale’s appropriate time representation. 21:30:00 (en_US)
21:30:00 (de_DE)
%% A literal ‘%’ character. %
指示 描述 示例输出
%一个 工作日为语言环境的缩写名称。 周日,周一,…,周六(en_US)
%一个 工作日为语言环境的全名。 周日,周一,…,周六(zh_CN)
%w 以十进制数表示的工作日,其中0是星期日,6是星期六。 0、1、2、3、4、5、6
%d 月份中的一天,以零填充的十进制数字表示。 01,02,…,31
%b 月作为语言环境的缩写名称。 一月,二月,…,十二月(en_US)
%B 月作为语言环境的全名。 一月,二月,…,十二月(zh_CN)
%m 以零填充的十进制数字表示的月份。 01,02…12
%y 无世纪的年份,为零填充的十进制数字。 01,02,…99
%Y 以世纪作为十进制数字的年份。 0001、0002,…,9999
%H 小时(24小时制),为补零的十进制数字。 01,02,…,23
%一世 小时(12小时制),为零填充的十进制数字。 01,02,…,12
%p 相当于AM或PM的语言环境。 上午,下午(en_US)
%M 分钟,为零填充的十进制数字。 01,02,…,59
%S 第二个为零填充的十进制数。 01,02,…,59
%F 微秒,十进制数,在左侧补零。 000000,000001,…,999999
%z UTC偏移量,格式为±HHMM [SS](如果对象是天真对象,则为空字符串)。 (空),+ 0000,-0400,+ 1030
%Z 时区名称(如果对象是天真对象,则为空字符串)。 (空),UTC,IST,CST
%j 一年中的一天,为零填充的十进制数字。 001,002,…,366
%U 一年中的周号(星期日为一周的第一天),以零填充的十进制数表示。
%W 一年中的星期数(星期一为一周的第一天),以十进制数表示。
%C 语言环境的适当日期和时间表示。 星期二八月16 21:30:00 1988(zh_CN)
Di 16 Aug 21:30:00 1988(de_DE)
%X 语言环境的适当日期表示形式。 88年8月16日(无)
%X 语言环境的适当时间表示形式。 21:30:00(zh_CN)
%% 文字“%”字符。

Python strptime()示例 (Python strptime() examples)

Let’s look into some specific examples of strptime() function to convert string to datetime and time objects.


字符串到日期时间 (String to datetime)

  1. from datetime import datetime
  3. datetime_str = '09/19/18 13:55:26'
  5. datetime_object = datetime.strptime(datetime_str, '%m/%d/%y %H:%M:%S')
  7. print(type(datetime_object))
  8. print(datetime_object) # printed in default format



  1. <class 'datetime.datetime'>
  2. 2018-09-19 13:55:26

字符串到日期对象 (String to date object)

We can use date() function alongwith strptime() function to convert string to date object.


  1. date_str = '09-19-2018'
  3. date_object = datetime.strptime(date_str, '%m-%d-%Y').date()
  4. print(type(date_object))
  5. print(date_object) # printed in default formatting



  1. <class ''>
  2. 2018-09-19

时间对象的字符串 (String to time object)

We can use time() function alongwith strptime() function to convert string to time object.


  1. time_str = '13::55::26'
  2. time_object = datetime.strptime(time_str, '%H::%M::%S').time()
  3. print(type(time_object))
  4. print(time_object)



  1. <class 'datetime.time'>
  2. 13:55:26

Python时间strptime()示例 (Python time strptime() example)

Let’s see some examples of using time module strptime() function.


  1. import time
  3. time_obj = time.strptime(time_str, '%H::%M::%S')
  4. print(type(time_obj))
  5. print(time_obj)
  7. # default formatting - "%a %b %d %H:%M:%S %Y"
  8. print(time.strptime('Wed Sep 19 14:55:02 2018'))



  1. <class 'time.struct_time'>
  2. time.struct_time(tm_year=1900, tm_mon=1, tm_mday=1, tm_hour=13, tm_min=55, tm_sec=26, tm_wday=0, tm_yday=1, tm_isdst=-1)
  3. time.struct_time(tm_year=2018, tm_mon=9, tm_mday=19, tm_hour=14, tm_min=55, tm_sec=2, tm_wday=2, tm_yday=262, tm_isdst=-1)

Python strptime()ValueError示例 (Python strptime() ValueError Example)

We can use try-except block to catch parsing exception and perform corrective actions.


  1. datetime_str = '09/19/18 13:55:26'
  3. try:
  4. datetime_object = datetime.strptime(datetime_str, '%m/%d/%y')
  5. except ValueError as ve:
  6. print('ValueError Raised:', ve)
  8. time_str = '99::55::26'
  10. try:
  11. time_object = time.strptime(time_str, '%H::%M::%S')
  12. except ValueError as e:
  13. print('ValueError:', e)



  1. ValueError Raised: unconverted data remains: 13:55:26
  2. ValueError: time data '99::55::26' does not match format '%H::%M::%S'

Notice that the ValueError message clearly explains the root cause of the parsing exception.


Python使用区域设置将字符串转换为日期时间 (Python Convert String to Datetime with locale)

Let’s look at an example where a locale-specific string will be converted to datetime object. We will use locale module to set the locale to be used by python.

让我们看一个示例,其中将特定于语言环境的字符串转换为datetime对象。 我们将使用语言环境模块来设置要由python使用的语言环境。

  1. import locale
  3. locale.setlocale(locale.LC_ALL, 'de_DE')
  4. date_str_de_DE = '10-Dezember-2018 Montag' # de_DE locale
  5. datetime_object = datetime.strptime(date_str_de_DE, '%d-%B-%Y %A')
  6. print(datetime_object)

Output: 2018-12-10 00:00:00

输出: 2018-12-10 00:00:00

posted @ 2021-07-02 15:42  蘭亭客  阅读(455)  评论(0编辑  收藏  举报