Python时间，日期，时间戳之间转换

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