装饰器

定义：本质是函数（装饰器他函数）为了其他函数添加附加功能

原则：1、不能修改被装饰的函数的源代码

           2、不能修改被装饰的函数的调用方式

实现装饰器需要掌握的点：

1、函数即“变量”

2、高阶函数

3、嵌套函数

装饰器=高阶函数+嵌套函数

 

 1 #!usr/bin/python
 2 #_*_coding:utf-8*_  
 3 #author:moll
 4 import time
 5 #第一个版本：
 6 username="moll"
 7 password="123"
 8 def decorator(authr_type):
 9     print("type is %s"%authr_type)
10     def outer_decorator(func):
11         def wapper(*args,**kwargs):
12             print(*args,**kwargs)
13             use = input("input the user:").strip()
14             pwd = input("input the pwd:").strip()
15             if authr_type=="local01":
16                 if use==username and pwd==password:
17                     print("you are right")
18                     res =func(*args,**kwargs)
19                     print("返回结果为-----------------------")
20                     return res
21                 else:
22                     exit("valid datas")
23             elif authr_type=="local02":
24                 print("搞毛线，dab")
25             else:
26                 print("一切都结束了")
27         return wapper
28     return outer_decorator
29 
30 @decorator(authr_type="local01")
31 def index():
32     print("welcome to inxdex")
33     return "today is monday"
34 @decorator(authr_type="local02")
35 def home():
36     print("welcome to home")
37     return "today is sunday"
38 @decorator(authr_type="local03")
39 def bbs():
40     print("welcome to bbs")
41 print(index())
42 home()
43 bbs()
44 
45 #第二个版本：
46 username="moll"
47 password="1"
48 def author(author_type):
49     def outer_wapper(func):
50         print("the author_type is %s"%author_type)
51         def timer(*args,**kwargs):
52 
53             user=input("input the username:")
54             pwd=input("input the password")
55             if author_type == "local01":
56                 if user=="moll" and pwd=="1":
57                     res=func(*args,**kwargs)
58                     print("you are right")
59                     return res
60                 else:
61                     exit("valid data")
62             elif author_type=="local02":
63                 print("没有")
64             else:
65                 print("大大地没有")
66         return timer
67     return outer_wapper
68 #装饰器传递装饰器的类型，根据不同的类型进行判断
69 @author(author_type="local01")
70 def index():
71     print("welcome to index")
72     return "index"
73 @author(author_type="local02")
74 def home():
75     print("welcome to home")
76 
77 @author(author_type="local03")
78 def bbs():
79     print("welocom to bbs")
80 
81 print(index())
82 home()
83 bbs()
View Code

 

posted @ 2018-11-12 23:48  mollsweet  阅读(61)  评论(0)    收藏  举报