Python沒(méi)有switch語(yǔ)句，只能通過(guò)模擬來(lái)對(duì)應(yīng)實(shí)現(xiàn)：

方法一：使用dictionary

**values = {value1: do_some_stuff1,value2: do_some_stuff2,...valueN: do_some_stuffN,}values.get(var, do_default_stuff)()

根據(jù)需求可以自行更改參數(shù)內(nèi)容，靈活運(yùn)用

def add(x,y): print x+y def minus(x,y): print x-y def multiply(x,y): print x*y def div(x,y): print x/y def fun_case_list(key,arg1,arg2): operator = { ’+’:add, ’-’:minus, ’*’:multiply, ’/’:div } if operator.has_key(key): return operator.get(key)(arg1,arg2) else: return ’No [%s] case in dic’%key #or do other funcif __name__ == '__main__': fun_case_list(’*’,3,5) fun_case_list(’l’,3,4)

或者你可以自己造一個(gè)類來(lái)實(shí)現(xiàn):

class switch_case(object): def case_to_function(self,case,arg1,arg2): func_name = ’case_func_’+str(case) try: method = getattr(self,func_name) return method(arg1,arg2) except AttributeError: return ’No func found in case list,do default action here’ def case_func_add(self,arg1,arg2): temp = arg1 + arg2 return temp def case_func_minus(self,arg1,arg2): temp = arg1 - arg2 return temp def case_func_multiply(self,arg1,arg2): temp = arg1 * arg2 return temp def case_func_div(self,arg1,arg2): temp = arg1 / arg2 return tempfunc = ’minus’case = switch_case()print case.case_to_function(func,2,5)#或者是構(gòu)造屬性去送參數(shù),看個(gè)人喜好class switch_case(object): def __init__(self, case, arg1, arg2): self.case = str(case) self.arg1 = arg1 self.arg2 = arg2 def case_to_function(self): func_name = ’case_func_’+str(self.case) try: method = getattr(self,func_name) return method() except AttributeError: return ’No func found in case list,do default action here’ def case_func_add(self): temp = self.arg1 + self.arg2 return temp def case_func_minus(self): temp = self.arg1 - self.arg2 return temp def case_func_multiply(self): temp = self.arg1 * self.arg2 return temp def case_func_div(self): temp = self.arg1 / self.arg2 return tempfunc = ’minxus’case = switch_case(func,2,5)print case.case_to_function()

方法二：使用lambda

result = {’a’: lambda x: x * 5,’b’: lambda x: x + 7,’c’: lambda x: x - 2}[value](x)

方法三：Brian Beck提供了一個(gè)類 switch 來(lái)實(shí)現(xiàn)switch的功能

class switch(object): def __init__(self, value): self.value = value self.fall = False def __iter__(self): '''Return the match method once, then stop''' yield self.match raise StopIteration def match(self, *args): '''Indicate whether or not to enter a case suite''' if self.fall or not args: return True elif self.value in args: # changed for v1.5, see below self.fall = True return True else: return Falsev = ’two’for case in switch(v): if case(’one’): print 1 break if case(’two’): print 2 break if case(’ten’): print 10 break if case(’eleven’): print 11 break if case(): # default, could also just omit condition or ’if True’ print 'something else!' # No need to break here, it’ll stop anyway

以上就是本文的全部?jī)?nèi)容，希望對(duì)大家的學(xué)習(xí)有所幫助，也希望大家多多支持好吧啦網(wǎng)。