Eleventh day: Time and Date

A, datetime

1、date

2、time

import datetime
datetime.MAXYEAR
datetime.MINYEAR
today = datetime.date.today()
today
today.year
today.month
today.day
today.weekday()
today.isoweekday()

9999
1
datetime.date(2019, 9, 7)
2019
9
7
5
6

3、datetime

• year
• month
• day

birthdate = datetime.date(2010, 3, 12)
birthdate.year
birthdate.day
t = datetime.time(15, 46, 32)
t.hour
t.minute
t.second

2010
12
15
46
32

import datetime
now = datetime.datetime.now()
now
now.year
now.second
now.microsecond #微秒

datetime.datetime(2019, 9, 7, 20, 14, 45, 543196)
2019
7
45
543196

4, format conversion

• String Date Time to datetime.datetime.strptime ( 'txt', '% Y-% m-% d')
• Datetime to string datetime.datetime.strftime ( '% Y /% m /% d')

import datetime
s = '2018-2-23'
t = datetime.datetime.strptime(s, '%Y-%m-%d') #Y要大写
t
now = datetime.datetime.now()
now
txt = now.strftime('%Y/%m/%d')
txt

datetime.datetime(2018, 2, 23, 0, 0)
datetime.datetime(2019, 9, 7, 20, 19, 16, 226808)
'2019/09/07'

• Placeholder
  % Y four years
  % y two years
  % m two month
  % d two dates
  % H two hours
  % M two minutes
  % S two seconds
  % f microseconds
  % w -0-6 weeks

  5, the time difference timedelta

import datetime
d = datetime.datetime(2018, 3, 5, 22, 44)
birthdate = datetime.datetime(2016, 5, 2, 19, 33, 44)
d - birthdate #相隔了672天11416秒

datetime.timedelta(days=672, seconds=11416)

• days
• seconds
• hours

diff = d - birthdate
diff.days
diff.seconds 
diff.total_seconds() #实际相隔的秒数

672
11416
58072216.0

o = datetime.datetime(2008, 8, 8, 20, 8)
o + datetime.timedelta(days=100)
result = d + datetime.timedelta(days = -100)
result
d + datetime.timedelta(seconds=3000)

datetime.datetime(2008, 11, 16, 20, 8)
datetime.datetime(2017, 11, 25, 22, 44)
datetime.datetime(2018, 3, 5, 23, 34)