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

    def addDay(date, number):
        for i in range(number)
            #try to add a day
            try:
                date = date.replace(day = date.day + 1)
            #in case it's impossible ex:january 32nd add a month and restart at day 1
            except:
                #add month part
                try:
                    date = date.replace(month = date.month +1, day = 1)
                except:
                    date = date.replace(year = date.year +1, month = 1, day = 1)

写给还在读这篇文章的人。我认为这段代码更加清晰,特别是与使用模(%)的代码相比。

很抱歉有语法错误,英语不是我的主要语言

其他回答

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

PyQt4的QDate类有一个addmonths函数。

>>>from PyQt4.QtCore import QDate  
>>>dt = QDate(2009,12,31)  
>>>required = dt.addMonths(6) 

>>>required
PyQt4.QtCore.QDate(2010, 6, 30)

>>>required.toPyDate()
datetime.date(2010, 6, 30)

我是这样解决这个问题的:

import calendar
from datetime import datetime
moths2add = 6
now = datetime.now()
current_year = now.year
current_month = now.month
#count days in months you want to add using calendar module
days = sum(
  [calendar.monthrange(current_year, elem)[1] for elem in range(current_month, current_month + moths)]
    )
print now + days

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

这并没有回答具体的问题(仅使用datetime),但是,鉴于其他人建议使用不同的模块,这里有一个使用pandas的解决方案。

import datetime as dt
import pandas as pd

date = dt.date.today() - \
       pd.offsets.DateOffset(months=6)

print(date)

2019-05-04 00:00:00

在闰年哪种方式会正常工作

date = dt.datetime(2019,8,29) - \
       pd.offsets.DateOffset(months=6)
print(date)

2019-02-28 00:00:00