【python】datetime获取日期,前一天日期

1.获取字符串型当前日期 2016-10-09格式

import datetime
today = datetime.date.today()   #datetime.date类型当前日期
str_today = str(today)   #字符串型当前日期

2.获取datetime.datetime类型当前日期

from datetime import datetime, date, timedelta
def getDatetimeToday(self):
        t = date.today()  #date类型
        dt = datetime.strptime(str(t),'%Y-%m-%d') #date转str再转datetime
        return dt

3.获取datetime.datetime类型前一天日期

from datetime import datetime, date, timedelta
def getDatetimeYesterday(self):
        today = self.getDatetimeToday() #datetime类型当前日期
        yesterday = today + timedelta(days = -1) #减去一天
        return yesterday