Python日期

1. datatime

from datetime import datetime, date

now = datetime.now()
print(now)  # 2020-01-20 01:24:01.843183

to = date.today()
print(to)  # 2020-01-20

print(datetime(2000, 1, 1, 1, 0, 0))  # 2000-01-01 01:00:00

delta = now - datetime(2000, 1, 1, 1, 0, 0)
print(now, type(now))  # 2020-01-20 01:24:01.843183 <class 'datetime.datetime'>

print(now.date())  # 2020-01-20

print(now.time())  # 2020-01-20

print(delta)  # 7324 days, 0:24:01.843183

print(delta.days)  # 7324

1.1 strptime

from datetime import datetime
S=datetime.strptime('2019/07/07','%Y/%m/%d')
print(S,type(S))
S=datetime.strptime('2019年7月7日星期日','%Y年%m月%d日星期日')
print(S,type(S))
S=datetime.strptime('2019年7月7日星期日8时42分24秒','%Y年%m月%d日星期日%H时%M分%S秒')
print(S,type(S))
S=datetime.strptime('7/7/2019','%m/%d/%Y')
print(S,type(S))
S=datetime.strptime('7/7/2019 8:42:50','%m/%d/%Y %H:%M:%S')
print(S,type(S))

#结果：
2019-07-07 00:00:00 <class 'datetime.datetime'>
2019-07-07 00:00:00 <class 'datetime.datetime'>
2019-07-07 08:42:24 <class 'datetime.datetime'>
2019-07-07 00:00:00 <class 'datetime.datetime'>
2019-07-07 08:42:50 <class 'datetime.datetime'>　

1.2 strftime

dt=datetime.now()
s=dt.strftime('%m/%d/%Y %H:%M:%S %p')
print(s,type(s))
s=dt.strftime('%A,%B %d,%Y')
print(s,type(s))
txt =('%s年%s月%s日星期%s %s时%s分%s秒'%(dt.strftime('%Y'),dt.strftime('%m'),dt.strftime('%d'),\<br>dt.strftime('%w'),dt.strftime('%H'),dt.strftime('%M'),dt.strftime('%S')))
print(txt)
s=dt.strftime('%B %d,%Y')
print(s,type(s))

结果：
07/07/2019 14:57:17 PM <class 'str'>
Sunday,July 07,2019 <class 'str'>
2019年07月07日星期0 14时57分17秒
July 07,2019 <class 'str'>

2. time

import time

# （1）当前时间戳
# time.time()
one = time.time()
print(one)  # 1579454251.8242934

# （2）时间戳 → 元组时间
two = time.localtime(time.time())
print(two)  # time.struct_time(tm_year=2020, tm_mon=1, tm_mday=20, tm_hour=1, tm_min=17, tm_sec=31, tm_wday=0, tm_yday=20, tm_isdst=0)

# （3）时间戳 → 可视化时间
three = time.ctime(time.time())
print(three)  # Mon Jan 20 01:17:31 2020

# （4）元组时间 → 时间戳
four = time.mktime(two)
print(four)  # 1579454251.0

# （5）元组时间 → 可视化时间
five = time.asctime()
print(five)  # Mon Jan 20 01:17:31 2020

# （6）时间元组 → 可视化时间（定制）
six = time.strftime("%Y-%m-%d %H:%M:%S", time.localtime())
print(six)  # 2020-01-20 01:17:31

# （7）可视化时间（定制） → 时间元祖
print("时间元祖:", time.strptime('2019-7-7 11:32:23', '%Y-%m-%d %H:%M:%S'))
# 时间元祖: time.struct_time(tm_year=2019, tm_mon=7, tm_mday=7, tm_hour=11, tm_min=32, tm_sec=23, tm_wday=6, tm_yday=188, tm_isdst=-1)

# （8）将格式字符串转换为时间戳
eight = "Sun Jul  7 10:48:24 2019"
print(time.mktime(time.strptime(eight, "%a %b %d %H:%M:%S %Y")))
# 1562467704.0