Python 学习入门（10）—— 时间

saundy

　　Python格式化日期时间的函数为datetime.datetime.strftime()；由字符串转为日期型的函数为：datetime.datetime.strptime()，两个函数都涉及日期时间的格式化字符串，列举如下：

%a  Abbreviated weekday name
%A  Full weekday name
%b  Abbreviated month name
%B  Full month name
%c  Date and time representation appropriate for locale
%d Day of month as decimal number (01 - 31)
%H  Hour in 24-hour format (00 - 23)
%I  Hour in 12-hour format (01 - 12)
%j  Day of year as decimal number (001 - 366)
%m  Month as decimal number (01 - 12)
%M  Minute as decimal number (00 - 59)
%p  Current locale's A.M./P.M. indicator for 12-hour clock
%S  Second as decimal number (00 - 59)
%U  Week of year as decimal number, with Sunday as first day of week (00 - 51)
%w  Weekday as decimal number (0 - 6; Sunday is 0)
%W  Week of year as decimal number, with Monday as first day of week (00 - 51)
%x  Date representation for current locale
%X  Time representation for current locale
%y  Year without century, as decimal number (00 - 99)
%Y Year with century, as decimal number
%z, %Z  Time-zone name or abbreviation; no characters if time zone is unknown
%%  Percent sign

　　

　　示例：

#!/usr/bin/python
# it-homer in 2013
import sys
reload(sys)
sys.setdefaultencoding("utf-8")
import datetime
def format_time():
t = datetime.datetime.now()
print(t)       # 2013-11-20 09:36:51.198680
t = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')
print(t)       # 2013-11-20 09:39:16
t = datetime.datetime.now().strftime('%b-%d-%y %H:%M:%S')
print(t)       # Nov-20-13 09:36:51
t = datetime.datetime.now().strftime('%b-%d-%Y %H:%M:%S')
print(t)       # Nov-20-2013 09:36:51
# weekday
t = datetime.datetime.now().strftime('%a %A %U %W %w')
print(t)      # Wed Wednesday 46 46 3
# month
t = datetime.datetime.now().strftime('%b %B')
print(t)       # Nov November
# day
t = datetime.datetime.now().strftime('%d %j')
print(t)       # 20 324
# date and time for locale
t = datetime.datetime.now().strftime('%c')
print(t)       # Wed Nov 20 10:15:49 2013
# hour
t = datetime.datetime.now().strftime('%H %l')
print(t)       # 10 10
# A.M/P.M
t = datetime.datetime.now().strftime('%p')
print(t)       # AM
t = datetime.datetime.now().strftime('%x')
print(t)       # 11/20/13
t = datetime.datetime.now().strftime('%X')
print(t)       # 10:23:36
t = datetime.datetime.now().strftime('%x %X')
print(t)       # 11/20/13 10:24:47
t = datetime.datetime.now().strftime('%z')
print(t)       #
t = datetime.datetime.now().strftime('%Z')
print(t)       #

# 字符串转换成datetime
t = datetime.datetime.strptime('Nov-20-13 09:42', '%b-%d-%y %H:%M')
print(t)      # 2013-11-20 09:42:00
t = datetime.datetime(2013, 11, 20, 9, 42)
print(t)      # 2013-11-20 09:42:00
# datetime转换成字符串
t = datetime.datetime.now().strftime('%b-%d-%y %H:%M:%S')
print(t)      # Nov-20-13 10:26:40

if __name__ == "__main__":
format_time()
　　


运行结果：　　2013-11-20 10:29:26.456640
2013-11-20 10:29:26
Nov-20-13 10:29:26
Nov-20-2013 10:29:26
Wed Wednesday 46 46 3
Nov November
20 324
Wed Nov 20 10:29:26 2013
10 10
AM
11/20/13
10:29:26
11/20/13 10:29:26


2013-11-20 09:42:00
2013-11-20 09:42:00
Nov-20-13 10:29:26