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Python中*args 和**kwargs的用法

当函数的参数不确定时,可以使用*args 和**kwargs,*args 没有key值,**kwargs有key值。

还是直接来代码吧,废话少说

[python] 

def fun_var_args(farg, *args): 

    print "arg:", farg 

    for value in args: 

        print "another arg:", value 

fun_var_args(1, "two", 3) # *args可以当作可容纳多个变量组成的list 

result:

arg: 1 

another arg: two 

another arg: 3 

**kwargs:

def fun_var_kwargs(farg, **kwargs): 

    for key in kwargs: 

        print "another keyword arg: %s: %s" % (key, kwargs[key]) 

fun_var_kwargs(farg=1, myarg2="two", myarg3=3) # myarg2和myarg3被视为key, 感觉**kwargs可以当作容纳多个key和value的dictionary 

another keyword arg: myarg2: two 

another keyword arg: myarg3: 3 

也可以用下面的形式:

def fun_var_args_call(arg1, arg2, arg3): 

    print "arg1:", arg1 

    print "arg2:", arg2 

    print "arg3:", arg3 

args = ["two", 3] #list 

fun_var_args_call(1, *args) 

result:

arg1: 1 

arg2: two 

arg3: 3 

kwargs = {"arg3": 3, "arg2": "two"} # dictionary 

fun_var_args_call(1, **kwargs) 

[python] view plaincopyprint?

arg2:"two" 

arg3:3