Python 利用*args和**kwargs解決函數遇到不肯定數量參數問題

當函數遇到不肯定數量參數腫麼破？*args和**kwargs前來報道！

 

*args       **kwargs

當函數的參數不肯定時，可使用*args 和**kwargs，*args 沒有key值，**kwargs有key值。

>>>def fun_var_args(farg, *args):
>>>    print "arg:", farg
>>>    for value in args:
>>>        print "another arg:", value

>>>fun_var_args(1, "two", 3)              # *args能夠看成可容納多個變量組成的list

result:
arg: 1
another arg: two
another arg: 3

**kwargs:

>>>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被視爲key， 感受**kwargs能夠看成容納多個key和value的dictionary

result:
arg: 1
another keyword arg: myarg2: two
another keyword arg: myarg3: 3