c#学习笔记-深度复制 与浅度复制

 关于值类型和引用类型：

 

浅度复制(shallow copy)只复制值类型(char,int )的值，而对于引用类型不会复制，浅度复制可以通过派生于system.object的memberwiseclone()方法来完成，这是一个受保护的方法。因为他并没有考虑引用类型成员，因此新对象的引用成员就会指向源对象中的相同成员引用的对象

如果要创建成员的新实例(复制值，而不是复制引用)就需要用到深度复制(deep copy)

深度复制需要实现一个icloneable接口，如果使用这个接口需要实现它包含的clone()方法，这个方法返回一个system.object的值，

下面看下浅度复制：

 1 public class company
 2     {
 3         public string value { get; set; }
 4     }
 5 
 6     public class phone
 7     {
 8        public string color { get; set; }
 9 
10        public  company company = new company();
11 
12         public phone (string newcompany)
13         {
14             company.value = newcompany;
15         }
16 
17         public object getcopy()
18         {
19             return memberwiseclone();
20         }
21     }

 1  static void main(string[] args)
 2         {
 3             phone phone = new phone("xiaomi");
 4             phone.color = "red";
 5             phone phone1 = (phone)phone.getcopy();            
 6             console.writeline($"phone company:{phone.company.value} color: {phone.color}");
 7             console.writeline($"phone1 company:{phone1.company.value} color: {phone1.color}");
 8 
 9             console.writeline("浅度复制修改新对象的值");
10 
11             phone1.company.value = "huawei";
12             phone1.color = "green";
13             console.writeline($"phone company:{phone.company.value} color: {phone.color}");
14             console.writeline($"phone1 company:{phone1.company.value} color: {phone1.color}");
15             console.readkey();
16 
17         }

实验现象：

浅度复制在后引用类型修改后，原对象也跟着发生了改变

修改这个问题，可以使用深度复制

 1 public class company
 2     {
 3         public string value { get; set; }
 4     }
 5 
 6     public class phone:icloneable
 7     {
 8        public string color { get; set; }
 9 
10        public  company company = new company();
11 
12         public phone (string newcompany)
13         {
14             company.value = newcompany;
15         }
16 
17         public object getcopy()
18         {
19             return memberwiseclone();
20         }
21 
22         public object clone()
23         {
24             phone newphone = new phone(company.value);
25             return newphone;
26             //newphone.company.value = this.company.value;
27 
28         }
29     }

 

 1 static void main(string[] args)
 2         {
 3             phone phone = new phone("xiaomi");
 4             phone.color = "red";
 5             phone phone1 = (phone)phone.clone();            
 6             console.writeline($"phone company:{phone.company.value} color: {phone.color}");
 7             console.writeline($"phone1 company:{phone1.company.value} color: {phone1.color}");
 8 
 9             console.writeline("浅度复制修改新对象的值");
10 
11             phone1.company.value = "huawei";
12             phone1.color = "green";
13             console.writeline($"phone company:{phone.company.value} color: {phone.color}");
14             console.writeline($"phone1 company:{phone1.company.value} color: {phone1.color}");
15             console.readkey();
16 
17         }

 

实验现象