我使用这个函数来更改年和月，但保留日:

def replace_month_year(date1, year2, month2):
    try:
        date2 = date1.replace(month = month2, year = year2)
    except:
        date2 = datetime.date(year2, month2 + 1, 1) - datetime.timedelta(days=1)
    return date2

你应该这样写:

new_year = my_date.year + (my_date.month + 6) / 12
new_month = (my_date.month + 6) % 12
new_date = replace_month_year(my_date, new_year, new_month)

Python可以使用datautil包，请参阅下面的示例

它不仅限于此，你还可以同时通过日、月和年的组合。

import datetime
from dateutil.relativedelta import relativedelta

# subtract months
proc_dt = datetime.date(2021,8,31)
proc_dt_minus_3_months = proc_dt + relativedelta(months=-3)
print(proc_dt_minus_3_months)

# add months
proc_dt = datetime.date(2021,8,31)
proc_dt_plus_3_months = proc_dt + relativedelta(months=+3)
print(proc_dt_plus_3_months)

# subtract days:
proc_dt = datetime.date(2021,8,31)
proc_dt_minus_3_days = proc_dt + relativedelta(days=-3)
print(proc_dt_minus_3_days)

# add days days:
proc_dt = datetime.date(2021,8,31)
proc_dt_plus_3_days = proc_dt + relativedelta(days=+3)
print(proc_dt_plus_3_days)

# subtract years:
proc_dt = datetime.date(2021,8,31)
proc_dt_minus_3_years = proc_dt + relativedelta(years=-3)
print(proc_dt_minus_3_years)

# add years:
proc_dt = datetime.date(2021,8,31)
proc_dt_plus_3_years = proc_dt + relativedelta(years=+3)
print(proc_dt_plus_3_years)

结果:

2021-05-31

2021-11-30

2021-08-28

2021-09-03

2018-08-31

2024-08-31

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)

修改了Johannes Wei在1new_month = 121情况下的答案。这对我来说非常合适。月份可以是正的，也可以是负的。

def addMonth(d,months=1):
    year, month, day = d.timetuple()[:3]
    new_month = month + months
    return datetime.date(year + ((new_month-1) / 12), (new_month-1) % 12 +1, day)

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

我知道这是6个月，但是如果你要添加一个月，答案在谷歌中显示为“在python中添加月”:

import calendar

date = datetime.date.today()    //Or your date

datetime.timedelta(days=calendar.monthrange(date.year,date.month)[1])

这将计算当前月份的天数，并将它们添加到当前日期，如果您在日期上迭代，则使用365/12将AD年的1/12会导致短/长月份出现问题。