我正在使用datetime Python模块。我希望从当前日期计算6个月的日期。有人能帮我一下吗?
我想从当前日期生成一个6个月后的日期的原因是为了生成一个回顾日期。如果用户在系统中输入数据,系统将有从输入数据之日起6个月的审查日期。
我正在使用datetime Python模块。我希望从当前日期计算6个月的日期。有人能帮我一下吗?
我想从当前日期生成一个6个月后的日期的原因是为了生成一个回顾日期。如果用户在系统中输入数据,系统将有从输入数据之日起6个月的审查日期。
当前回答
我的实现基于taleinat的答案:
import datetime
import calendar
def add_months(orig_date, month_count = 1):
while month_count > 12:
month_count -= 12
orig_date = add_months(orig_date, 12)
new_year = orig_date.year
new_month = orig_date.month + month_count
# note: in datetime.date, months go from 1 to 12
if new_month > 12:
new_year += 1
new_month -= 12
last_day_of_month = calendar.monthrange(new_year, new_month)[1]
new_day = min(orig_date.day, last_day_of_month)
return orig_date.replace(year=new_year, month=new_month, day=new_day)
有了这个功能,你可以添加任意多的月份。
from datetime import date
dt = date(2021, 1, 31)
print(add_months(dt, 49))
返回 2025-02-28
其他回答
import datetime
'''
Created on 2011-03-09
@author: tonydiep
'''
def add_business_months(start_date, months_to_add):
"""
Add months in the way business people think of months.
Jan 31, 2011 + 1 month = Feb 28, 2011 to business people
Method: Add the number of months, roll back the date until it becomes a valid date
"""
# determine year
years_change = months_to_add / 12
# determine if there is carryover from adding months
if (start_date.month + (months_to_add % 12) > 12 ):
years_change = years_change + 1
new_year = start_date.year + years_change
# determine month
work = months_to_add % 12
if 0 == work:
new_month = start_date.month
else:
new_month = (start_date.month + (work % 12)) % 12
if 0 == new_month:
new_month = 12
# determine day of the month
new_day = start_date.day
if(new_day in [31, 30, 29, 28]):
#user means end of the month
new_day = 31
new_date = None
while (None == new_date and 27 < new_day):
try:
new_date = start_date.replace(year=new_year, month=new_month, day=new_day)
except:
new_day = new_day - 1 #wind down until we get to a valid date
return new_date
if __name__ == '__main__':
#tests
dates = [datetime.date(2011, 1, 31),
datetime.date(2011, 2, 28),
datetime.date(2011, 3, 28),
datetime.date(2011, 4, 28),
datetime.date(2011, 5, 28),
datetime.date(2011, 6, 28),
datetime.date(2011, 7, 28),
datetime.date(2011, 8, 28),
datetime.date(2011, 9, 28),
datetime.date(2011, 10, 28),
datetime.date(2011, 11, 28),
datetime.date(2011, 12, 28),
]
months = range(1, 24)
for start_date in dates:
for m in months:
end_date = add_business_months(start_date, m)
print("%s\t%s\t%s" %(start_date, end_date, m))
使用Python标准库,即没有dateutil或其他,并解决“2月31日”问题:
import datetime
import calendar
def add_months(date, months):
months_count = date.month + months
# Calculate the year
year = date.year + int(months_count / 12)
# Calculate the month
month = (months_count % 12)
if month == 0:
month = 12
# Calculate the day
day = date.day
last_day_of_month = calendar.monthrange(year, month)[1]
if day > last_day_of_month:
day = last_day_of_month
new_date = datetime.date(year, month, day)
return new_date
测试:
>>>date = datetime.date(2018, 11, 30)
>>>print(date, add_months(date, 3))
(datetime.date(2018, 11, 30), datetime.date(2019, 2, 28))
>>>print(date, add_months(date, 14))
(datetime.date(2018, 12, 31), datetime.date(2020, 2, 29))
我认为这样做会比手动添加天数更安全:
import datetime
today = datetime.date.today()
def addMonths(dt, months = 0):
new_month = months + dt.month
year_inc = 0
if new_month>12:
year_inc +=1
new_month -=12
return dt.replace(month = new_month, year = dt.year+year_inc)
newdate = addMonths(today, 6)
我插话晚了,但是
查看肯雷茨玛雅模块,
https://github.com/kennethreitz/maya
像这样的方法可能会对你有帮助,只需将小时=1改为天=1或年=1
>>> from maya import MayaInterval
# Create an event that is one hour long, starting now.
>>> event_start = maya.now()
>>> event_end = event_start.add(hours=1)
>>> event = MayaInterval(start=event_start, end=event_end)
只需使用timetuple方法提取月份,添加您的月份并构建一个新的dateobject。如果有一个已经存在的方法,我不知道它。
import datetime
def in_the_future(months=1):
year, month, day = datetime.date.today().timetuple()[:3]
new_month = month + months
return datetime.date(year + (new_month / 12), (new_month % 12) or 12, day)
这个API有点笨拙,但可以作为示例使用。这显然也不适用于像2008-01-31 + 1个月这样的极端情况。:)