copy 浅拷贝和深拷贝

Posted 2020-11-11 独孤_败天

 1 #直接赋值和 copy 的区别
 2 dic1={‘name‘: ‘Tom‘, ‘age‘: 18, ‘hobby‘: ‘running‘}
 3 dic2=dic1
 4 
 5 print(dic1)
 6 print(dic2)
 7 
 8 #修改数据 age=28
 9 dic1[‘age‘]=28
10 
11 print(dic1)
12 print(dic2)
13 # 浅拷贝: 引用对象   dic2只是对dic1的引用。所以当dic1的值改变，dic2也会随着改变
14 
15 
16 dic3={‘name‘: ‘Tom‘, ‘age‘: 18, ‘hobby‘: ‘running‘}
17 
18 dic4=dic3.copy()
19 #浅拷贝：深拷贝父对象（一级目录），子对象（二级目录）不拷贝，还是引用
20 print(dic3)
21 print(dic4)
22 #修改数据 age=38
23 dic3[‘age‘]=38
24 
25 print(dic3)
26 print(dic4)
27 
28 dic5={‘name‘: [‘Tom‘,‘Jack‘], ‘age‘:[ 18,28], ‘hobby‘: [‘running‘,‘football‘]}
29 
30 dic6=dic5.copy()
31 
32 #浅拷贝：深拷贝父对象（一级目录），子对象（二级目录）不拷贝，还是引用
33 print(dic5)
34 print(dic6)
35 #修改一级目录（父对象），修改数据  [‘running‘,‘football‘]修改为[‘basketball‘]
36 dic5[‘hobby‘]=[‘basketball‘,]
37 
38 #修改二级目录（子对象），修改数据  Tom 改成 May
39 dic5[‘name‘][0]=‘May‘
40 dic5[‘age‘][0]=38
41 
42 print(dic5)
43 print(dic6)

结果：

{‘name‘: ‘Tom‘, ‘age‘: 18, ‘hobby‘: ‘running‘}
{‘name‘: ‘Tom‘, ‘age‘: 18, ‘hobby‘: ‘running‘}

{‘name‘: ‘Tom‘, ‘age‘: 28, ‘hobby‘: ‘running‘}
{‘name‘: ‘Tom‘, ‘age‘: 28, ‘hobby‘: ‘running‘}

{‘name‘: ‘Tom‘, ‘age‘: 18, ‘hobby‘: ‘running‘}
{‘name‘: ‘Tom‘, ‘age‘: 18, ‘hobby‘: ‘running‘}

{‘name‘: ‘Tom‘, ‘age‘: 38, ‘hobby‘: ‘running‘}
{‘name‘: ‘Tom‘, ‘age‘: 18, ‘hobby‘: ‘running‘}

{‘name‘: [‘Tom‘, ‘Jack‘], ‘age‘: [18, 28], ‘hobby‘: [‘running‘, ‘football‘]}
{‘name‘: [‘Tom‘, ‘Jack‘], ‘age‘: [18, 28], ‘hobby‘: [‘running‘, ‘football‘]}

{‘name‘: [‘May‘, ‘Jack‘], ‘age‘: [38, 28], ‘hobby‘: [‘basketball‘]}
{‘name‘: [‘May‘, ‘Jack‘], ‘age‘: [38, 28], ‘hobby‘: [‘running‘, ‘football‘]}