time有四种类型(time, datetime, string, timestamp)
1. time string
string是最简单的表示time的方式
如如下代码生成的即为string
1 2 3 | >>> import time>>> time.ctime()'Wed Nov 30 13:53:31 2016' |
或者更简单的生成一个字符串
1 | time_string = '2016-11-30 13:54:05' |
2. datetime tuple(datetime obj)
datetime tuple是datetime.datetime对象类型
1 2 3 | >>> import datetime>>> datetime.datetime.now()datetime.datetime(2016, 11, 30, 13, 56, 51, 984213) |
3. time tuple(time obj)
time tuple是time.struct_time对象类型
1 2 3 | >>> date_str = "2016-11-30 13:53:59">>> time.strptime(date_str, "%Y-%m-%d %H:%M:%S")time.struct_time(tm_year=2016, tm_mon=11, tm_mday=30, tm_hour=13, tm_min=53, tm_sec=59, tm_wday=2, tm_yday=335, tm_isdst=-1) |
4. timestamp
时间戳类型:自1970年1月1日(00:00:00 GMT)以来的秒数
1 2 3 | >>> import time>>> time.time()1480485476.20922 |
time, datetime, string, timestamp相互转换
1. string 转换为其它
初始化:
date_str = "2016-11-30 13:53:59"
1.1 string --> datetime obj
1 2 3 4 | >>> import datetime>>> date_str = "2016-11-30 13:53:59">>> datetime.datetime.strptime(date_str, "%Y-%m-%d %H:%M:%S")datetime.datetime(2016, 11, 30, 13, 53, 59) |
1.2 string --> time obj
1 2 3 4 | >>> import time>>> date_str = "2016-11-30 13:53:59">>> time.strptime(date_str, "%Y-%m-%d %H:%M:%S")time.struct_time(tm_year=2016, tm_mon=11, tm_mday=30, tm_hour=13, tm_min=53, tm_sec=59, tm_wday=2, tm_yday=335, tm_isdst=-1) |
2. datetime obj转换为其它
datetime obj转换为其它类型,用的都是datetime的函数
初始化:
dt_obj = datetime.datetime(2016, 11, 30, 13, 53, 59)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 | 格式字符 意义%a 星期的简写。如 星期三为Web%A 星期的全写。如 星期三为Wednesday%b 月份的简写。如4月份为Apr%B 月份的全写。如4月份为April%c: 日期时间的字符串表示。(如: 04/07/10 10:43:39)%d: 日在这个月中的天数(是这个月的第几天)%f: 微秒(范围[0,999999])%H: 小时(24小时制,[0, 23])%I: 小时(12小时制,[0, 11])%j: 日在年中的天数 [001,366](是当年的第几天)%m: 月份([01,12])%M: 分钟([00,59])%p: AM或者PM%S: 秒(范围为[00,61],为什么不是[00, 59],参考python手册~_~)%U: 周在当年的周数当年的第几周),星期天作为周的第一天%w: 今天在这周的天数,范围为[0, 6],6表示星期天%W: 周在当年的周数(是当年的第几周),星期一作为周的第一天%x: 日期字符串(如:04/07/10)%X: 时间字符串(如:10:43:39)%y: 2个数字表示的年份%Y: 4个数字表示的年份%z: 与utc时间的间隔 (如果是本地时间,返回空字符串)%Z: 时区名称(如果是本地时间,返回空字符串)%%: %% => % |
2.1 dt obj --> string
1 2 3 4 | >>> import datetime>>> dt_obj = datetime.datetime(2016, 11, 30, 13, 53, 59)>>> dt_obj.strftime("%Y-%m-%d %H:%M:%S")'2016-11-30 13:53:59' |
2.2 dt obj --> time obj
1 2 3 4 | >>> import datetime>>> dt_obj = datetime.datetime(2016, 11, 30, 13, 53, 59)>>> dt_obj.timetuple()time.struct_time(tm_year=2016, tm_mon=11, tm_mday=30, tm_hour=13, tm_min=53, tm_sec=59, tm_wday=2, tm_yday=335, tm_isdst=-1) |
3. time obj转换为其它
初始化:
time_tuple = (2016, 11, 30, 13, 51, 18, 2, 317, 0)
3.1 time obj --> string
1 2 3 4 | >>> import time>>> time_tuple = (2016, 11, 30, 13, 51, 18, 2, 317, 0)>>> time.strftime("%Y-%m-%d %H:%M:%S", time_tuple)'2016-11-30 13:51:18' |
3.2 time obj --> datetime obj
1 2 3 4 | >>> import time, datetime>>> time_tuple = (2016, 11, 30, 13, 51, 18, 2, 317, 0)>>> datetime.datetime(*time_tuple[0:6])datetime.datetime(2016, 11, 30, 13, 51, 18) |
3.3 time obj --> timestamp
1 2 3 4 | >>> import time>>> time_tuple = (2016, 11, 30, 13, 51, 18, 2, 317, 0)>>> time.mktime(time_tuple)1480485078.0 |
4. timestamp转换为其它
初始化:
timestamp = 1480486369.75
--!!--注意以下两种都使用local时区
4.1 timestamp --> dt obj
1 2 3 4 | >>> import datetime>>> timestamp = 1480486369.75>>> datetime.datetime.fromtimestamp(timestamp)datetime.datetime(2016, 11, 30, 14, 12, 49, 750000) |
4.2 timestamp --> time obj
1 2 3 4 | >>> import time>>> timestamp = 1480486369.75>>> time.localtime(timestamp)time.struct_time(tm_year=2016, tm_mon=11, tm_mday=30, tm_hour=14, tm_min=12, tm_sec=49, tm_wday=2, tm_yday=335, tm_isdst=0) |
--!!--以下两种方式和时区相关,比较标准时区时间和本地时区时间
4.3 使用UTC --> dt obj
#本地时区时间
1 2 3 4 | >>> import datetime>>> timestamp = 1480486369.75>>> datetime.datetime.fromtimestamp(timestamp)datetime.datetime(2016, 11, 30, 14, 12, 49, 750000) |
#标准时区时间
1 2 3 4 | >>> import datetime>>> timestamp = 1480486369.75>>> datetime.datetime.utcfromtimestamp(timestamp)datetime.datetime(2016, 11, 30, 6, 12, 49, 750000) |
4.4 使用UTC --> time obj
#本地时区时间
1 2 3 4 | >>> import time>>> timestamp = 1480486369.75>>> time.localtime(timestamp)time.struct_time(tm_year=2016, tm_mon=11, tm_mday=30, tm_hour=14, tm_min=12, tm_sec=49, tm_wday=2, tm_yday=335, tm_isdst=0) |
#标准时区时间
1 2 3 4 | >>> import datetime>>> timestamp = 1480486369.75>>> time.gmtime(timestamp)time.struct_time(tm_year=2016, tm_mon=11, tm_mday=30, tm_hour=6, tm_min=12, tm_sec=49, tm_wday=2, tm_yday=335, tm_isdst=0) |