python 日期加减

import datetime, time from dateutil.relativedelta import relativedelta # 执行pip install python-dateutil 安装python-dateutil模块，进行日期的加减处理 #relativedelta(years=+1, months=+1, days=+1,hours=+1, minutes=+1, seconds=+1)，可进行不同维度时间的加减 # 与当前相差天数 def get_diff_days_2_now(date_str): now_time = time.localtime(time.time()) compare_time = time.strptime(date_str, "%Y-%m-%d") # 比较日期 date1 = datetime.datetime(compare_time[0], compare_time[1], compare_time[2]) date2 = datetime.datetime(now_time[0], now_time[1], now_time[2]) diff_days = (date2 - date1).days # 上面是正确的获取方法，返回一个int类型天差值，修改时间：2019年8月25日 # diff_days = str(date2 - date1) # # 如果相差0天单纯显示为 00:00:00 不然显示为 [diff_days] : 00:00:00 # diff_days_arr = diff_days.split(":") # if len(diff_days_arr) == 1: # return 0 # else: # return diff_days_arr[0].split()[0] return diff_days # 获得指定差值的某一天 def get_specified_date(date, diff): # 字符串转日期 sdate = datetime.datetime.strptime(date, '%Y-%m-%d') # 加上指定的天数，可以为负 # delta = sdate + relativedelta(days=diff) # 日期转为字符串 specified_date = delta.strftime("%Y-%m-%d") return specified_date # 获得指定差值的某月 def get_specified_month(date, diff): sdate = datetime.datetime.strptime(date, '%Y-%m-%d') # 加上指定的月数，可以为负 delta = sdate + relativedelta(months=diff) specified_date = delta.strftime("%Y-%m-%d") return specified_date # 获得指定差值的某月 def get_specified_year(date, diff): sdate = datetime.datetime.strptime(date, '%Y-%m-%d') # 加上指定的年数，可以为负 delta = sdate + relativedelta(years=diff) specified_date = delta.strftime("%Y-%m-%d") return specified_date ​