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
*args
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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
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result:
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arg: 1
another arg: two
another arg: 3
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**kwargs:
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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
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result:
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arg: 1
another keyword arg: myarg2: two
another keyword arg: myarg3: 3
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也可以用下面的形式
*args的另外一种方式
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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)
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result:
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arg1: 1
arg2: two
arg3: 3
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**kwargs的另外一种方式
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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)
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result:
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arg1: 1
arg2:“two”
arg3:3
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