Python的switch方法

        C/C++程序员习惯用switch语句，但python是没有的。那么python如何处理多分支情况呢？方法一是使用if--elif--elif--else，显然分支越多，判断越多，不是最优；那么下面介绍最优的方法二——使用字典映射来实现switch/case方法。

>>> #-*- coding: utf-8 -*->>> import time>>> now = time.localtime()>>> print nowtime.struct_time(tm_year=2017, tm_mon=9, tm_mday=10, tm_hour=10, tm_min=38, tm_sec=43, tm_wday=6, tm_yday=253, tm_isdst=0)>>> print time.strftime('%Y-%m-%d %H:%M:%S',now)2017-09-10 10:38:43>>> def long_time_cn(t):print time.strftime('%Y-%m-%d %H:%M:%S',t)>>> def long_time_en(t):print time.strftime('%B %d %Y %H:%M:%S',t)>>> def short_time_cn(t):print time.strftime('%y-%#m-%#d %#H:%#M',t)>>> def short_time_en(t):print time.strftime('%b %#d %y %#H:%#M',t)>>> timelist = {'cnl':long_time_cn,'enl':long_time_en,'cns':short_time_cn,'ens':short_time_en}>>> def mytime(outputmothod,outputtime):try:t = timelist.get(outputmothod)(outputtime)        return texcept Exception,e:print '%s' %(e)>>> mytime('cnl',now)2017-09-10 10:38:43>>> mytime('cns',now)17-9-10 10:38>>> mytime('ens',now)Sep 10 17 10:38>>> mytime('enl',now)September 10 2017 10:38:43>>> mytime('ennnn',now)'NoneType' object is not callable>>> mytime(1,now)'NoneType' object is not callable>>>