【python进阶】*args 和 **kwargs的用法

比眉伴天荒 2022-03-27 02:06 294阅读 0赞

参考链接：[https://eastlakeside.gitbooks.io/interpy-zh/content/args\_kwargs/Usage\_args.html][https_eastlakeside.gitbooks.io_interpy-zh_content_args_kwargs_Usage_args.html]

变量名不是最重要的，前面两个\*才是最重要的。

# \*args用法 #

\*args用来发送一个非键值对的可变数量的参数列表给一个函数

def test_var(*args):
        for arg in args:
            print(arg, end=" ")
        print()
    test_var(1,2,3,4,5)

输出：  
![在这里插入图片描述][20190111170628690.png]

--------------------

# \*\*kwargs用法 #

python format函数用法，用中括号表示  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNjM3Mjg3OQ_size_16_color_FFFFFF_t_70]

def greet_me(**kwargs):
        for key, value in kwargs.items():
            print("{0} hello {1}".format(key, value))
    greet_me(acd='abs')

![在这里插入图片描述][2019011117181651.png]

--------------------

# \*args和\*\*kwrgs调用函数 #

def test_args_kwargs(arg1, arg2, arg3):
        print("arg1:", arg1)
        print("arg2:", arg2)
        print("arg3:", arg3)
    args = ("tow",2,3)
    test_args_kwargs(*args)

![在这里插入图片描述][2019011117445079.png]  
如果args里面有四个参数的话：

args = ("tow",2,3,4)
    test_args_kwargs(*args)

这样就会报错  
![在这里插入图片描述][20190111174541391.png]

def test_args_kwargs(arg1, arg2, arg3):
        print("arg1:", arg1)
        print("arg2:", arg2)
        print("arg3:", arg3)
    #args = ("tow",2,3)
    #test_args_kwargs(*args)
    kwargs = { "arg3": 3, "arg2": "two", "arg1": 5}
    test_args_kwargs(**kwargs)

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNjM3Mjg3OQ_size_16_color_FFFFFF_t_70 1]

[https_eastlakeside.gitbooks.io_interpy-zh_content_args_kwargs_Usage_args.html]: https://eastlakeside.gitbooks.io/interpy-zh/content/args_kwargs/Usage_args.html
[20190111170628690.png]: /images/20220327/2df0e8c2ace64d8eb5ae0870c6b2fd16.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNjM3Mjg3OQ_size_16_color_FFFFFF_t_70]: /images/20220327/5ca65328b1cd4a7a910ba56953131870.png
[2019011117181651.png]: /images/20220327/c6387d947d0c45cface07a3ab7e83548.png
[2019011117445079.png]: /images/20220327/877850e3826140d9abb9b404d77c9e5f.png
[20190111174541391.png]: /images/20220327/8334832193ce4996a275f0371fe86918.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNjM3Mjg3OQ_size_16_color_FFFFFF_t_70 1]: /images/20220327/5291f0c6b99647068624c700755973b8.png