Summary of usage examples of Python variable parameters *args and **kwargs

This article mainly introduces the usage of Python variable parameters *args and **kwargs. It summarizes and analyzes the functions, differences and specific usage skills of variable parameters *args and **kwargs in Python in the form of examples. Friends who need it You can refer to the following

The examples in this article describe the usage of Python variable parameters *args and **kwargs. Share it with everyone for your reference, the details are as follows:

A simple summary in one sentence: When the parameters of the function are uncertain, you need to use *args and **kwargs, The difference between the former and the latter is that the latter introduces a "variable" key Concept, while the former does not have the concept of key, please refer to the following usage examples and specific explanations:

#!usr/bin/env python
#encoding:utf-8
'''''
__Author__:沂水寒城
功能：*args 和 **kwargs
'''
def test_func1(*args):
  '''''
  *args
  当函数的参数数量不确定的时候可以使用*args，个人理解*args相当于一个大小可变地列表
  容器，有点类似于C语言中的指针，传给引用即可找到内容，在这里可以使用*+变量的形式
  来实现内容可变列表的输出
  '''
  for index, one_char in enumerate(args):
    print 'index={0}, one_char={1}'.format(index, one_char)
def test_func2(**kwargs):
  '''''
  **kwargs
  这个和上面的功能性质是一样的，只是*args没有key的概念，**kwargs加入了可变key的操作
  这个参数允许你使用未定义的参数名而不会出现KeyError
  '''
  for id_num, name in kwargs.items():
    print '{0}:{1}'.format(id_num,name)
def print_dict(one_dict):
  '''''
  直接输出字典内容
  '''
  for id_num, name in one_dict.items():
    print id_num, name
if __name__ == '__main__':
  print "脚本之家测试结果："
  str_list=['沂','水','寒','城','We','Are','Friends']
  str_dict={'id_num':20123456, 'name':'yishuihancheng'}
  test_func1(*str_list)
  test_func2(**str_dict)
  print '-----------------------------------------------------------'
  print_dict(str_dict)

The results are as follows :

Script House test results:
index=0, one_char=悂
index=1, one_char=水
index=2, one_char=Han
index =3, one_char=城
index=4, one_char=We
index=5, one_char=Are
index=6, one_char=Friends
id_num:20123456
name:yishuihancheng
------------------------------------------------ ----------
id_num 20123456
name yishuihancheng

Screenshot of running results:

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