如何将以下字符串转换为datetime对象?

"Jun 1 2005  1:33PM"

当前回答

如果您只需要日期格式,则可以通过传递单个字段(如:

>>> import datetime
>>> date = datetime.date(int('2017'),int('12'),int('21'))
>>> date
datetime.date(2017, 12, 21)
>>> type(date)
<type 'datetime.date'>

您可以传递拆分字符串值,将其转换为日期类型,如:

selected_month_rec = '2017-09-01'
date_formate = datetime.date(int(selected_month_rec.split('-')[0]),int(selected_month_rec.split('-')[1]),int(selected_month_rec.split('-')[2]))

您将获得日期格式的结果值。

其他回答

我个人喜欢使用解析器模块的解决方案,这是这个问题的第二个答案,非常漂亮,因为您不必构造任何字符串文字就能使其工作。但是,一个缺点是它比strptime的公认答案慢了90%。

from dateutil import parser
from datetime import datetime
import timeit

def dt():
    dt = parser.parse("Jun 1 2005  1:33PM")
def strptime():
    datetime_object = datetime.strptime('Jun 1 2005  1:33PM', '%b %d %Y %I:%M%p')

print(timeit.timeit(stmt=dt, number=10**5))
print(timeit.timeit(stmt=strptime, number=10**5))

输出:

10.702968013429021.3627995655316933

只要你不反复做一百万次,我仍然认为解析器方法更方便,并且可以自动处理大多数时间格式。

我已经完成了一个项目,可以转换一些非常整洁的表达式。查看时间字符串。

以下是一些示例:

pip install timestring
>>> import timestring
>>> timestring.Date('monday, aug 15th 2015 at 8:40 pm')
<timestring.Date 2015-08-15 20:40:00 4491909392>
>>> timestring.Date('monday, aug 15th 2015 at 8:40 pm').date
datetime.datetime(2015, 8, 15, 20, 40)
>>> timestring.Range('next week')
<timestring.Range From 03/10/14 00:00:00 to 03/03/14 00:00:00 4496004880>
>>> (timestring.Range('next week').start.date, timestring.Range('next week').end.date)
(datetime.datetime(2014, 3, 10, 0, 0), datetime.datetime(2014, 3, 14, 0, 0))

这里没有提到但很有用的一点:在当天添加后缀。我解耦了后缀逻辑,这样你就可以将它用于任何你喜欢的数字,而不仅仅是日期。

import time

def num_suffix(n):
    '''
    Returns the suffix for any given int
    '''
    suf = ('th','st', 'nd', 'rd')
    n = abs(n) # wise guy
    tens = int(str(n)[-2:])
    units = n % 10
    if tens > 10 and tens < 20:
        return suf[0] # teens with 'th'
    elif units <= 3:
        return suf[units]
    else:
        return suf[0] # 'th'

def day_suffix(t):
    '''
    Returns the suffix of the given struct_time day
    '''
    return num_suffix(t.tm_mday)

# Examples
print num_suffix(123)
print num_suffix(3431)
print num_suffix(1234)
print ''
print day_suffix(time.strptime("1 Dec 00", "%d %b %y"))
print day_suffix(time.strptime("2 Nov 01", "%d %b %y"))
print day_suffix(time.strptime("3 Oct 02", "%d %b %y"))
print day_suffix(time.strptime("4 Sep 03", "%d %b %y"))
print day_suffix(time.strptime("13 Nov 90", "%d %b %y"))
print day_suffix(time.strptime("14 Oct 10", "%d %b %y"))​​​​​​​

Django时区感知日期时间对象示例。

import datetime
from django.utils.timezone import get_current_timezone
tz = get_current_timezone()

format = '%b %d %Y %I:%M%p'
date_object = datetime.datetime.strptime('Jun 1 2005  1:33PM', format)
date_obj = tz.localize(date_object)

当USE_TZ=True时,这种转换对于Django和Python非常重要:

RuntimeWarning: DateTimeField MyModel.created received a naive datetime (2016-03-04 00:00:00) while time zone support is active.

如果您不想明确指定字符串相对于日期时间格式的格式,可以使用此黑客绕过该步骤:

from dateutil.parser import parse

# Function that'll guess the format and convert it into the python datetime format
def update_event(start_datetime=None, end_datetime=None, description=None):
    if start_datetime is not None:
        new_start_time = parse(start_datetime)

        return new_start_time

# Sample input dates in different formats
d = ['06/07/2021 06:40:23.277000', '06/07/2021 06:40', '06/07/2021']

new = [update_event(i) for i in d]

for date in new:
    print(date)
    # Sample output dates in Python datetime object
    #   2014-04-23 00:00:00
    #   2013-04-24 00:00:00
    #   2014-04-25 00:00:00

如果要将其转换为其他日期时间格式,只需使用您喜欢的格式修改最后一行,例如date.strftime(“%Y/%m/%d%H:%m:%S.%f”):

from dateutil.parser import parse

def update_event(start_datetime=None, end_datetime=None, description=None):
    if start_datetime is not None:
        new_start_time = parse(start_datetime)

        return new_start_time

# Sample input dates in different formats
d = ['06/07/2021 06:40:23.277000', '06/07/2021 06:40', '06/07/2021']

# Passing the dates one by one through the function
new = [update_event(i) for i in d]

for date in new:
    print(date.strftime('%Y/%m/%d %H:%M:%S.%f'))
    # Sample output dates in required Python datetime object
    #   2021/06/07 06:40:23.277000
    #   2021/06/07 06:40:00.000000
    #   2021/06/07 00:00:00.000000

尝试运行上面的代码段以获得更好的清晰度。