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:
[python] 
arg: 1 
another arg: two 
another arg: 3 
**kwargs:
[python] 
def fun_var_kwargs(farg, **kwargs): 
    print "arg:", farg 
    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 
result:
[python] 
arg: 1 
another keyword arg: myarg2: two 
another keyword arg: myarg3: 3 
也可以用下面的形式:
[python] 
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:
[python] 
arg1: 1 
arg2: two 
arg3: 3

[python] 
def fun_var_args_call(arg1, arg2, arg3): 
    print "arg1:", arg1 
    print "arg2:", arg2 
    print "arg3:", arg3 
 
kwargs = {"arg3": 3, "arg2": "two"} # dictionary 
 
fun_var_args_call(1, **kwargs) 
result:
[python] view plaincopyprint?
arg1: 1 
arg2:"two" 
arg3:3

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