Python 日期格式相关

#-*- coding: gb2312 -*-
import datetime, time

#now = time.strftime('%Y年%m月%d日 %H时%M分%S秒', time.localtime()).decode('utf-8')
now = time.strftime('%Y年%m月%d日 %H时%M分%S秒', time.localtime())
print now

now = time.strptime(now, '%Y年%m月%d日 %H时%M分%S秒')
print now
print time.strftime('%Y-%m-%d %H:%M:%S', now)

2015年01月21日 14时22分12秒
time.struct_time(tm_year=2015, tm_mon=1, tm_mday=21, tm_hour=14, tm_min=22, tm_sec=12, tm_wday=2, tm_yday=21, tm_isdst=-1)
2015-01-21 14:22:12

>>> time.strftime('%Y-%m-%d %H:%M:%S', time.localtime())
'2015-01-21 14:32:31'
>>> datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
'2015-01-21 14:33:38'

>>> time.strptime("2015-1-2 11:22:33", '%Y-%m-%d %H:%M:%S')
time.struct_time(tm_year=2015, tm_mon=1, tm_mday=2, tm_hour=11, tm_min=22, tm_sec=33, tm_wday=4, tm_yday=2, tm_isdst=-1)
>>> datetime.datetime.strptime("2015-1-2 11:22:33", '%Y-%m-%d %H:%M:%S')
datetime.datetime(2015, 1, 2, 11, 22, 33)

>>> time.localtime(1234567890)
time.struct_time(tm_year=2009, tm_mon=2, tm_mday=14, tm_hour=7, tm_min=31, tm_sec=30, tm_wday=5, tm_yday=45, tm_isdst=0)
>>> datetime.date.fromtimestamp(1234567890)
datetime.date(2009, 2, 14)

>>> int(time.time())
1421822833
>>> time.mktime(datetime.date(2015,1,21).timetuple())
1421769600.0
>>> time.mktime(time.strptime("2015-1-21", "%Y-%m-%d"))
1421769600.0

>>> datetime.datetime.now() #今天
datetime.datetime(2015, 1, 21, 14, 53, 43, 321906)
>>> (datetime.datetime.now() - datetime.timedelta(days=3)).day #3天前
18
#timedelta支持的单位 days, seconds, microseconds, milliseconds, minutes, hours, weeks
>>> (datetime.datetime.now() - datetime.timedelta(weeks=1)).day
14