Object.MemberwiseClone 方法
创建当前 Object 的浅表副本。
**命名空间:**System
**程序集:**mscorlib（在 mscorlib.dll 中）
语法
声明
Protected Function MemberwiseClone As Object
用法
Dim returnValue As Object
returnValue = Me.MemberwiseClone
protected Object MemberwiseClone ()
protected:
Object^ MemberwiseClone ()
protected Object MemberwiseClone ()
protected function MemberwiseClone () : Object
返回值
当前 Object 的浅表副本。
备注
MemberwiseClone 方法创建一个浅表副本，方法是创建一个新对象，然后将当前对象的非静态字段复制到该新对象。如果字段是值类型的，则对该字段执行逐位复制。如果字段是引用类型，则复制引用但不复制引用的对象；因此，原始对象及其复本引用同一对象。
例如，考虑一个名为 X 的对象，该对象引用对象 A 和 B。对象 B 又引用对象 C。X 的浅表副本创建一个新对象 X2，该对象也引用对象 A 和 B。与此相对照，X 的深层副本创建一个新对象 X2，该对象引用新对象 A2 和 B2，它们分别是 A 和 B 的副本。B2 又引用新对象 C2，C2 是 C 的副本。使用实现 ICloneable 接口的类执行对象的浅表或深层复制。
示例
下面的代码示例说明如何使用 MemberwiseClone 复制类的实例。
Imports System
Class MyBaseClass
Public Shared CompanyName As String = "My Company"
Public age As Integer
Public name As String
End Class 'MyBaseClass
Class MyDerivedClass
Inherits MyBaseClass
Shared Sub Main()
' Creates an instance of MyDerivedClass and assign values to its fields.
Dim m1 As New MyDerivedClass()
m1.age = 42
m1.name = "Sam"
' Performs a shallow copy of m1 and assign it to m2.
Dim m2 As MyDerivedClass = CType(m1.MemberwiseClone(), MyDerivedClass)
End Sub 'Main
End Class 'MyDerivedClass
using System;
class MyBaseClass {
public static string CompanyName = "My Company";
public int age;
public string name;
}
class MyDerivedClass: MyBaseClass {
static void Main() {
// Creates an instance of MyDerivedClass and assign values to its fields.
MyDerivedClass m1 = new MyDerivedClass();
m1.age = 42;
m1.name = "Sam";
// Performs a shallow copy of m1 and assign it to m2.
MyDerivedClass m2 = (MyDerivedClass) m1.MemberwiseClone();
}
}
using namespace System;
ref class MyBaseClass
{
public:
static String^ CompanyName;
int age;
String^ name;
};
ref class MyDerivedClass: public MyBaseClass
{
public:
static void Test()
{
// Creates an instance of MyDerivedClass and assign values to its fields.
MyDerivedClass^ m1 = gcnew MyDerivedClass;
m1->age = 42;
m1->name = "Sam";
// Performs a shallow copy of m1 and assign it to m2.
MyDerivedClass^ m2 = safe_cast<MyDerivedClass^>(m1->MemberwiseClone());
}
};
int main()
{
MyDerivedClass::Test();
}
import System.*;
class MyBaseClass implements ICloneable
{
public static String companyName = "My Company";
public int age;
public String name;
} //MyBaseClass
class MyDerivedClass extends MyBaseClass
{
public static void main(String[] args) throws CloneNotSupportedException
{
// Creates an instance of MyDerivedClass and assign
// values to its fields.
MyDerivedClass m1 = new MyDerivedClass();
m1.age = 42;
m1.name = "Sam";
// Performs a shallow copy of m1 and assign it to m2.
MyDerivedClass m2 = (MyDerivedClass)m1.MemberwiseClone();
} //main
} //MyDerivedClass
import System
class MyBaseClass {
public static var CompanyName : String = "My Company";
public var age : int;
public var name : String;
}
class MyDerivedClass extends MyBaseClass {
static function Main() {
// Creates an instance of MyDerivedClass and assign values to its fields.
var m1 : MyDerivedClass = new MyDerivedClass();
m1.age = 42;
m1.name = "Sam";
// Performs a shallow copy of m1 and assign it to m2.
var m2 : MyDerivedClass = MyDerivedClass(m1.MemberwiseClone());
}
}
平台
Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Mobile for Smartphone、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition
.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。
版本信息
.NET Framework
受以下版本支持：2.0、1.1、1.0
.NET Compact Framework
受以下版本支持：2.0、1.0