模块学习-time,datetime模块

1 time.timezone #以秒为单位显示时区

>>> import time
>>> time.timezone
-28800

北京为东八区，所以为-28800

2 time.altzone #以秒为单位返回与UTC的时间差

>>> time.altzone
-32400

　　

3 time.daylight #返回夏时制，0代表不是夏时制，1代表是夏时制

>>> time.daylight
0

4 time.time() # 返回时间戳

>>> time.time()
1571626440.597493

5 time.sleep() #等待几秒

>>> time.sleep(3)
>>>

6 time.getime() #返回UTC struct_time,结果是个元祖

>>> time.gmtime()
time.struct_time(tm_year=2019, tm_mon=10, tm_mday=21, tm_hour=3, tm_min=1, tm_sec=11, tm_wday=0, t
m_yday=294, tm_isdst=0)
 
>>> time.gmtime(1000000000)
time.struct_time(tm_year=2001, tm_mon=9, tm_mday=9, tm_hour=1, tm_min=46, tm_sec=40, tm_wday=6, tm_yday=252, tm_isd
st=0)

7 time.localtime() #返回当地时间 struct_time

>>> time.localtime()#不加参数 默认返回当前时间
time.struct_time(tm_year=2019, tm_mon=10, tm_mday=21, tm_hour=11, tm_min=2, tm_sec=46, tm_wday=0,
tm_yday=294, tm_isdst=0)
 
>>> time.localtime(1000000000)#添加参数，根据参数计算
time.struct_time(tm_year=2001, tm_mon=9, tm_mday=9, tm_hour=9, tm_min=46, tm_sec=40, tm_wday=6, tm
_yday=252, tm_isdst=0)
 

8 获取struct_time数据

>>> x = time.localtime()
>>> x.tm_year
2019

9 struct_time转换为时间戳

>>> x = time.localtime()
>>> x
time.struct_time(tm_year=2019, tm_mon=10, tm_mday=21, tm_hour=11, tm_min=12, tm_sec=54, tm_wday=0, tm_yday=294, tm_
isdst=0)
>>> y = time.mktime(x)
>>> y
1571627574.0

10 格式化时间    struct_time --->格式化时间

>>> x = time.localtime()
>>> x
time.struct_time(tm_year=2019, tm_mon=10, tm_mday=21, tm_hour=11, tm_min=16, tm_sec=31, tm_wday=0, tm_yday=294, tm_
isdst=0)
>>> z = time.strftime('%Y-%m-%d %H:%M:%S',x)#先写格式 后传struct_time
>>> z
'2019-10-21 11:16:31'
>>>

格式化编码说明

Commonly used format codes:
 
    %Y  Year with century as a decimal number.
    %m  Month as a decimal number [01,12].
    %d  Day of the month as a decimal number [01,31].
    %H  Hour (24-hour clock) as a decimal number [00,23].
    %M  Minute as a decimal number [00,59].
    %S  Second as a decimal number [00,61].
    %z  Time zone offset from UTC.
    %a  Locale's abbreviated weekday name.
    %A  Locale's full weekday name.
    %b  Locale's abbreviated month name.
    %B  Locale's full month name.
    %c  Locale's appropriate date and time representation.
    %I  Hour (12-hour clock) as a decimal number [01,12].
    %p  Locale's equivalent of either AM or PM.

11 格式化时间    格式化时间 --->stuct_time

>>> a = time.strptime('2360-02-29 22:45:12','%Y-%m-%d %H:%M:%S')#先写格式化时间，在写格式
>>> a
time.struct_time(tm_year=2360, tm_mon=2, tm_mday=29, tm_hour=22, tm_min=45, tm_sec=12, tm_wday=0, tm_yday=60, tm_is
dst=-1)
>>>

12 便捷获取格式化时间

>>> b = time.asctime()#空参数默认返回当前时间
>>> b
'Mon Oct 21 11:22:13 2019'#默认格式就是这样  星期 月 日 小时 分钟 秒
 
>>> c = time.ctime()#同asctime()
>>> c
'Mon Oct 21 11:25:00 2019'

13 时间加减

>>> import datetime
>>> datetime.datetime.now()
datetime.datetime(2019, 10, 21, 11, 27, 2, 236054)
>>> datetime.datetime.now()+datetime.timedelta(3)
datetime.datetime(2019, 10, 24, 11, 29, 26, 657239)
>>> datetime.datetime.now()+datetime.timedelta(-3)
datetime.datetime(2019, 10, 18, 11, 30, 6, 553413)
>>> datetime.datetime.now()+datetime.timedelta(hours=3)