Python 学习笔记 -- 装饰器

1 #修饰符的作用就是为已经存在的对象添加额外的功能
 2 #实例:
 3 import time
 4 
 5 def timesLong(fun):
 6     x = 0
 7     def call():
 8         start = time.clock()
 9         print("时钟开始！")
10         fun()
11         end = time.clock()
12         print("时钟结束！")
13         return "函数运行累积用时 %s 秒" % (end - start)
14     return call
15 
16 @timesLong
17 def func():
18     x = 0
19     for i in range(100):
20         x += i
21 
22     print(x)
23 
24 print(func())
25 
26 #分析结果：
27 #实际上print(func()) = print(timesLong(func)())
28 #证明：
29 def func_test():
30     x = 0
31     for i in range(100):
32         x += i
33 
34     print(x)
35 
36 print(timesLong(func_test)())
37 #流程即：调用装饰器函数 --》 将佩戴装饰器的函数名传入其中
38 
39 #------------------------------------------------------------------
40 #property 装饰器版使用
41 
42 
43 class Code:
44     def __init__(self,size=10):
45         self.__size = size
46 
47     @property
48     def size(self):
49         return self.__size
50 
51     @size.setter
52     def size(self,value):
53         self.__size = value
54 
55     @size.deleter
56     def size(self):
57         del self.__size
58 
59 test = Code()
60 print(test.size)
61 test.size = 100
62 print(test.size)
63 del test.size
64 try:
65     print(test.size)
66 except:
67     print("test._Code__size 已被删除")      

转载于:https://www.cnblogs.com/jiangchenxi/p/8066847.html