python处理时间汇总

1.将字符串的时间转换为时间戳
方法:
a = "2013-10-10 23:40:00"
将其转换为时间数组
import time
timeArray = time.strptime(a, "%Y-%m-%d %H:%M:%S")
转换为时间戳:
timeStamp = int(time.mktime(timeArray))
timeStamp == 1381419600

2.字符串格式更改
如a = "2013-10-10 23:40:00",想改为 a = "2013/10/10 23:40:00"
方法:先转换为时间数组,然后转换为其他格式
timeArray = time.strptime(a, "%Y-%m-%d %H:%M:%S")
otherStyleTime = time.strftime("%Y/%m/%d %H:%M:%S", timeArray)


3.时间戳转换为指定格式日期:
方法一:
利用localtime()转换为时间数组,然后格式化为需要的格式,如
timeStamp = 1381419600
timeArray = time.localtime(timeStamp)
otherStyleTime = time.strftime("%Y-%m-%d %H:%M:%S", timeArray)
otherStyletime == "2013-10-10 23:40:00"

方法二:
import datetime
timeStamp = 1381419600
dateArray = datetime.datetime.utcfromtimestamp(timeStamp)
otherStyleTime = dateArray.strftime("%Y-%m-%d %H:%M:%S")
otherStyletime == "2013-10-10 23:40:00"

4.获取当前时间并转换为指定日期格式
方法一:
import time
获得当前时间时间戳
now = int(time.time()) ->这是时间戳
转换为其他日期格式,如:"%Y-%m-%d %H:%M:%S"
timeArray = time.localtime(timeStamp)
otherStyleTime = time.strftime("%Y-%m-%d %H:%M:%S", timeArray)

方法二:
import datetime
获得当前时间
now = datetime.datetime.now() ->这是时间数组格式
转换为指定的格式:
otherStyleTime = now.strftime("%Y-%m-%d %H:%M:%S")

5.获得三天前的时间
方法:
import time
import datetime
先获得时间数组格式的日期
threeDayAgo = (datetime.datetime.now() - datetime.timedelta(days = 3))
转换为时间戳:
timeStamp = int(time.mktime(threeDayAgo.timetuple()))
转换为其他字符串格式:
otherStyleTime = threeDayAgo.strftime("%Y-%m-%d %H:%M:%S")
注:timedelta()的参数有:days,hours,seconds,microseconds

6.给定时间戳,计算该时间的几天前时间:
timeStamp = 1381419600
先转换为datetime
import datetime
import time
dateArray = datetime.datetime.utcfromtimestamp(timeStamp)
threeDayAgo = dateArray - datetime.timedelta(days = 3)
参考5,可以转换为其他的任意格式了
7.按时区显示
import datetime
timeStamp = 1381419600
dateArray = datetime.datetime.utcfromtimestamp(timeStamp)
dateArray.strftime('%FT%T+0800')
dateArray.strftime('%FT%T.%fZ')