Python常用模块-时间模块

Posted 2020-10-26 尹正杰

　　　　　　　　　　　　　　　Python常用模块-时间模块（time & datetime）

　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　作者：尹正杰

版权声明：原创作品，谢绝转载！否则将追究法律责任。

 

 

 

一.初始time模块

 1 #！/usr/bin/env python
 2 #_*_coding:utf-8_*_
 3 #@author :yinzhengjie
 4 #blog:http://www.cnblogs.com/yinzhengjie/tag/python%E8%87%AA%E5%8A%A8%E5%8C%96%E8%BF%90%E7%BB%B4%E4%B9%8B%E8%B7%AF/
 5 #EMAIL:[e-mail]
 6 
 7 import time
 8 
 9 """"
10 模块的分类：
11     模块本质就是一个“*.py”文件，大致分为以下三类：
12         1>.内置模块,指的是存在Python解释器内部的模块，如time模块；
13         2>>第三方模块，指的是安装好Python后的lib文件夹中的模块；
14         3>.自定义模块，指的是你自己写的Python程序；
15 """
16 
17 print(time.time())      #返回当前的时间戳，表示从1971年1月1日"00:00:00"到此刻时间节点的秒数。
18 
19 s = time.localtime()    #创建一个时间对象，也可以说是在结构化时间对象,返回本地时间的struct_time对象格式。
20 print(s)
21 print(s.tm_year)        #获取年份。
22 print(s.tm_mon)         #获取月份。
23 
24 s2 = time.gmtime()      #返回utc时间的struc时间对象格式。
25 print(s2)
26 
27 
28 
29 
30 #以上代码执行结果如下：
31 1520176127.9244497
32 time.struct_time(tm_year=2018, tm_mon=3, tm_mday=4, tm_hour=23, tm_min=8, tm_sec=47, tm_wday=6, tm_yday=63, tm_isdst=0)
33 2018
34 3
35 time.struct_time(tm_year=2018, tm_mon=3, tm_mday=4, tm_hour=15, tm_min=8, tm_sec=47, tm_wday=6, tm_yday=63, tm_isdst=0)

二.时间模块的相互转换

1.转换助记图

 

2.案例展示

 1 #！/usr/bin/env python
 2 #_*_coding:utf-8_*_
 3 #@author :yinzhengjie
 4 #blog:http://www.cnblogs.com/yinzhengjie/tag/python%E8%87%AA%E5%8A%A8%E5%8C%96%E8%BF%90%E7%BB%B4%E4%B9%8B%E8%B7%AF/
 5 #EMAIL:[e-mail]
 6 
 7 import time
 8 
 9 s = time.localtime(31245244545)                         #结构化时间对象，可以将时间戳转换成结构化时间。
10 print(s)
11 
12 s2 = time.mktime(time.localtime())                      #将结构化时间转换成时间戳。
13 print(s2)
14 
15 s3 = time.strftime("%Y-%m-%d",time.localtime())        #将结构化时间转换成字符串时间。
16 print(s3)
17 
18 s4 = time.strptime("1993:05:19","%Y:%m:%d")         #将字符串时间转换成结构化时间。
19 print(s4)
20 
21 
22 
23 #以上代码执行结果如下：
24 time.struct_time(tm_year=2960, tm_mon=2, tm_mday=15, tm_hour=2, tm_min=35, tm_sec=45, tm_wday=4, tm_yday=46, tm_isdst=0)
25 1520176194.0
26 2018-03-04
27 time.struct_time(tm_year=1993, tm_mon=5, tm_mday=19, tm_hour=0, tm_min=0, tm_sec=0, tm_wday=2, tm_yday=139, tm_isdst=-1)

三.time扩充

 1 #！/usr/bin/env python
 2 #_*_coding:utf-8_*_
 3 #@author :yinzhengjie
 4 #blog:http://www.cnblogs.com/yinzhengjie/tag/python%E8%87%AA%E5%8A%A8%E5%8C%96%E8%BF%90%E7%BB%B4%E4%B9%8B%E8%B7%AF/
 5 #EMAIL:[e-mail]
 6 
 7 
 8 import time
 9 print(time.asctime(time.localtime()))           #将结构化时间转换成字符串时间。
10 print(time.ctime(565656446))                    #将时间戳转换成字符串时间。
11 
12 time.sleep(2)                                   #让程序暂停2秒钟，用于模拟I/O阻塞，并不占用CPU资源。
13 
14 
15 
16 
17 #以上代码执行结果如下：
18 Sun Mar  4 23:11:16 2018
19 Sat Dec  5 06:47:26 1987

四.time模块小试牛刀

 1 #！/usr/bin/env python
 2 #_*_coding:utf-8_*_
 3 #@author :yinzhengjie
 4 #blog:http://www.cnblogs.com/yinzhengjie/tag/python%E8%87%AA%E5%8A%A8%E5%8C%96%E8%BF%90%E7%BB%B4%E4%B9%8B%E8%B7%AF/
 5 #EMAIL:[e-mail]
 6 
 7 import time
 8 
 9 s = "2018-03-04"
10 
11 def ChangeTime(string,number,format="%Y-%m-%d"):
12     StructTime = time.strptime(string,format )
13     print(StructTime)
14     StampTime = time.mktime(StructTime)
15     print(StampTime)
16     NewStamp = StampTime + 3600 * 24 * number
17     NewStringTime = time.strftime(format, time.localtime(NewStamp))
18     print(NewStringTime)
19 
20 ChangeTime(s,3)     #推算3日后的时间
21 
22 
23 
24 
25 #以上代码执行结果如下：
26 time.struct_time(tm_year=2018, tm_mon=3, tm_mday=4, tm_hour=0, tm_min=0, tm_sec=0, tm_wday=6, tm_yday=63, tm_isdst=-1)
27 1520092800.0
28 2018-03-07

五.datetime介绍

 1 #！/usr/bin/env python
 2 #_*_coding:utf-8_*_
 3 #@author :yinzhengjie
 4 #blog:http://www.cnblogs.com/yinzhengjie/tag/python%E8%87%AA%E5%8A%A8%E5%8C%96%E8%BF%90%E7%BB%B4%E4%B9%8B%E8%B7%AF/
 5 #EMAIL:[e-mail]
 6 import time,datetime
 7 
 8 print(datetime.datetime.now())                                  #打印当前系统时间
 9 
10 print(datetime.date.fromtimestamp(time.time()))                 #时间戳直接转成日期格式如：2018-03-04
11 
12 print(datetime.datetime.now() + datetime.timedelta(3))          #当前时间+3天
13 
14 print(datetime.datetime.now() + datetime.timedelta(-3))         #当前时间-3天
15 
16 print(datetime.datetime.now() + datetime.timedelta(hours=3))    #当前时间+3小时
17 
18 print(datetime.datetime.now() + datetime.timedelta(minutes=30)) #当前时间+30分
19 
20 c_time  = datetime.datetime.now()
21 print(c_time.replace(minute=3,hour=2))                          ##时间替换
22 
23 
24 
25 
26 #以上代码执行结果如下：
27 2018-03-04 23:12:13.477416
28 2018-03-04
29 2018-03-07 23:12:13.477416
30 2018-03-01 23:12:13.477416
31 2018-03-05 02:12:13.477416
32 2018-03-04 23:42:13.477416
33 2018-03-04 02:03:13.477416

 六.关于格式化参数的详细说明

Directive	Meaning	Notes
%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.
%d	Day of the month as a decimal number [01,31].
%H	Hour (24-hour clock) as a decimal number [00,23].
%I	Hour (12-hour clock) as a decimal number [01,12].
%j	Day of the year as a decimal number [001,366].
%m	Month as a decimal number [01,12].
%M	Minute as a decimal number [00,59].
%p	Locale’s equivalent of either AM or PM.	(1)
%S	Second as a decimal number [00,61].	(2)
%U	Week number of the year (Sunday as the first day of the week) as a decimal number [00,53]. All days in a new year preceding the first Sunday are considered to be in week 0.	(3)
%w	Weekday as a decimal number [0(Sunday),6].
%W	Week number of the year (Monday as the first day of the week) as a decimal number [00,53]. All days in a new year preceding the first Monday are considered to be in week 0.	(3)
%x	Locale’s appropriate date representation.
%X	Locale’s appropriate time representation.
%y	Year without century as a decimal number [00,99].
%Y	Year with century as a decimal number.
%z	Time zone offset indicating a positive or negative time difference from UTC/GMT of the form +HHMM or -HHMM, where H represents decimal hour digits and M represents decimal minute digits [-23:59, +23:59].
%Z	Time zone name (no characters if no time zone exists).
%%	A literal \'%\' character.