时间模块

1.time 时间戳

2.datetime

3.python-deteutil(pip install)

常用的操作：

1.时间各种格式表示

2.各种加减运算

import time

time.time()  #时间戳

1533133461.6765099

start = time.time()
print(start)

1533133482.158626

end = time.time()
print(f‘过了 {end - start} 秒‘)

过了 73.09727120399475 秒

start = time.time()
# 执行各种操作
for i in range(100):  # 计算循环用了多长时间
    print(i)

end = time.time()
print(f‘过了{end - start} s‘)

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过了0.0 s

# time.sleep()
for i in range(5):
    time.sleep(1)
    print(i)

0
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# 结构化时间与时间戳的转换
time.localtime()  # 返回的是元祖

time.struct_time(tm_year=2018, tm_mon=8, tm_mday=1, tm_hour=22, tm_min=29, tm_sec=35, tm_wday=2, tm_yday=213, tm_isdst=0)

time.localtime(10) #距离1970年的时间转换

time.struct_time(tm_year=1970, tm_mon=1, tm_mday=1, tm_hour=8, tm_min=0, tm_sec=10, tm_wday=3, tm_yday=1, tm_isdst=0)

time.mktime(time.localtime())

1533134001.0

time.mktime(time.localtime())  # 返回的浮点数时间戳

1533134010.0

for i in range(10):
    time.sleep(1)
    print(time.mktime(time.localtime()))

1533134061.0
1533134062.0
1533134063.0
1533134064.0
1533134065.0
1533134066.0
1533134067.0
1533134068.0
1533134069.0
1533134070.0

# 结构化时间与字符串格式的转换
# 时间的字符串格式化：http://devdocs.io/python~3.6/library/time#time.strftime
# time.strftime?
‘‘‘
%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.
‘‘‘

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

# 结构化时间与字符串格式的转换
# 时间的字符串格式化
time.strftime("%Y-%m-%d %X", time.localtime())

‘2018-08-01 22:40:28‘

for i in range(5):
    time.sleep(1)
    print(time.strftime("%Y-%m-%d %X", time.localtime()))

2018-08-01 22:41:27
2018-08-01 22:41:28
2018-08-01 22:41:29
2018-08-01 22:41:30
2018-08-01 22:41:31

time.strptime("2018-08-01 22:41:31", "%Y-%m-%d %X")  #与上面的逆向转换

time.struct_time(tm_year=2018, tm_mon=8, tm_mday=1, tm_hour=22, tm_min=41, tm_sec=31, tm_wday=2, tm_yday=213, tm_isdst=-1)

for i in range(5):
    time.sleep(1)
    print(time.strptime("2018-08-01 22:41:31", "%Y-%m-%d %X"))

time.struct_time(tm_year=2018, tm_mon=8, tm_mday=1, tm_hour=22, tm_min=41, tm_sec=31, tm_wday=2, tm_yday=213, tm_isdst=-1)
time.struct_time(tm_year=2018, tm_mon=8, tm_mday=1, tm_hour=22, tm_min=41, tm_sec=31, tm_wday=2, tm_yday=213, tm_isdst=-1)
time.struct_time(tm_year=2018, tm_mon=8, tm_mday=1, tm_hour=22, tm_min=41, tm_sec=31, tm_wday=2, tm_yday=213, tm_isdst=-1)
time.struct_time(tm_year=2018, tm_mon=8, tm_mday=1, tm_hour=22, tm_min=41, tm_sec=31, tm_wday=2, tm_yday=213, tm_isdst=-1)
time.struct_time(tm_year=2018, tm_mon=8, tm_mday=1, tm_hour=22, tm_min=41, tm_sec=31, tm_wday=2, tm_yday=213, tm_isdst=-1)

时间模块

原文：http://blog.51cto.com/13118411/2153374