ObjectHandle 类
包装按值封送对象引用，从而使它们可以通过间接寻址返回。
**命名空间:**System.Runtime.Remoting
**程序集:**mscorlib（在 mscorlib.dll 中）
语法
声明
<ComVisibleAttribute(True)> _
<ClassInterfaceAttribute(ClassInterfaceType.AutoDual)> _
Public Class ObjectHandle
Inherits MarshalByRefObject
Implements IObjectHandle
用法
Dim instance As ObjectHandle
[ComVisibleAttribute(true)]
[ClassInterfaceAttribute(ClassInterfaceType.AutoDual)]
public class ObjectHandle : MarshalByRefObject, IObjectHandle
[ComVisibleAttribute(true)]
[ClassInterfaceAttribute(ClassInterfaceType::AutoDual)]
public ref class ObjectHandle : public MarshalByRefObject, IObjectHandle
/** @attribute ComVisibleAttribute(true) */
/** @attribute ClassInterfaceAttribute(ClassInterfaceType.AutoDual) */
public class ObjectHandle extends MarshalByRefObject implements IObjectHandle
ComVisibleAttribute(true)
ClassInterfaceAttribute(ClassInterfaceType.AutoDual)
public class ObjectHandle extends MarshalByRefObject implements IObjectHandle
备注
ObjectHandle 类用于在多个应用程序域之间传递对象（处于已包装状态），而不需要将已包装对象的元数据加载到 ObjectHandle 游历的每个 AppDomain 中。因此，ObjectHandle 类使调用方可以控制何时将远程对象的 Type 加载到域中。
示例
下面的代码示例显示如何在另一个 AppDomain 中创建对象并从 ObjectHandle 检索该对象的代理。在本示例中，可以假定 MyType 类的代码被编译为称为“ObjectHandleAssembly”的程序集中。
Imports System
Imports System.Runtime.Remoting
Public Class MyType
Inherits MarshalByRefObject
Public Sub New()
Console.Write("Created an instance of MyType in an AppDomain with the ")
Console.WriteLine("hashcode {0}", AppDomain.CurrentDomain.GetHashCode())
Console.WriteLine("")
End Sub 'New
Public Function GetAppDomainHashCode() As Integer
Return AppDomain.CurrentDomain.GetHashCode()
End Function 'GetAppDomainHashCode
End Class 'MyType
Class Test
Public Shared Sub Main()
Console.WriteLine("The hash code of the default AppDomain is {0}.", AppDomain.CurrentDomain.GetHashCode())
Console.WriteLine("")
' Creates another AppDomain.
Dim domain As AppDomain = AppDomain.CreateDomain("AnotherDomain", Nothing, CType(Nothing, AppDomainSetup))
' Creates an instance of MyType defined in the assembly called ObjectHandleAssembly.
Dim obj As ObjectHandle = domain.CreateInstance("ObjectHandleAssembly", "MyType")
' Unwrapps the proxy to the MyType object created in the other AppDomain.
Dim testObj As MyType = CType(obj.Unwrap(), MyType)
If RemotingServices.IsTransparentProxy(testObj) Then
Console.WriteLine("The unwrapped object is a proxy.")
Else
Console.WriteLine("The unwrapped object is not a proxy!")
End If
Console.WriteLine("")
Console.Write("Calling a method on the object located in an AppDomain with the hash code ")
Console.WriteLine(testObj.GetAppDomainHashCode())
End Sub 'Main
End Class 'Test
using System;
using System.Runtime.Remoting;
public class MyType : MarshalByRefObject {
public MyType() {
Console.Write("Created an instance of MyType in an AppDomain with the ");
Console.WriteLine("hash code {0}",AppDomain.CurrentDomain.GetHashCode());
Console.WriteLine("");
}
public int GetAppDomainHashCode() {
return AppDomain.CurrentDomain.GetHashCode();
}
}
class Test {
public static void Main() {
Console.WriteLine("The hash code of the default AppDomain is {0}.",
AppDomain.CurrentDomain.GetHashCode());
Console.WriteLine("");
// Creates another AppDomain.
AppDomain domain = AppDomain.CreateDomain("AnotherDomain",
null,
(AppDomainSetup)null);
// Creates an instance of MyType defined in the assembly called ObjectHandleAssembly.
ObjectHandle obj = domain.CreateInstance("ObjectHandleAssembly", "MyType");
// Unwrapps the proxy to the MyType object created in the other AppDomain.
MyType testObj = (MyType)obj.Unwrap();
if(RemotingServices.IsTransparentProxy(testObj))
Console.WriteLine("The unwrapped object is a proxy.");
else
Console.WriteLine("The unwrapped object is not a proxy!");
Console.WriteLine("");
Console.Write("Calling a method on the object located in an AppDomain with the hash code ");
Console.WriteLine(testObj.GetAppDomainHashCode());
}
}
using namespace System;
using namespace System::Runtime::Remoting;
public ref class MyType: public MarshalByRefObject
{
public:
MyType()
{
Console::Write( "Created an instance of MyType in an AppDomain with the " );
Console::WriteLine( "hash code {0}", AppDomain::CurrentDomain->GetHashCode() );
Console::WriteLine( "" );
}
int GetAppDomainHashCode()
{
return AppDomain::CurrentDomain->GetHashCode();
}
};
int main()
{
Console::WriteLine( "The hash code of the default AppDomain is {0}.", AppDomain::CurrentDomain->GetHashCode() );
Console::WriteLine( "" );
// Creates another AppDomain.
AppDomain^ domain = AppDomain::CreateDomain( "AnotherDomain", nullptr, (AppDomainSetup^)nullptr );
// Creates an instance of MyType defined in the assembly called ObjectHandleAssembly.
ObjectHandle^ obj = domain->CreateInstance( "ObjectHandleAssembly", "MyType" );
// Unwraps the proxy to the MyType object created in the other AppDomain.
MyType^ testObj = dynamic_cast<MyType^>(obj->Unwrap());
if ( RemotingServices::IsTransparentProxy( testObj ) )
Console::WriteLine( "The unwrapped object is a proxy." );
else
Console::WriteLine( "The unwrapped object is not a proxy!" );
Console::WriteLine( "" );
Console::Write( "Calling a method on the object located in an AppDomain with the hash code " );
Console::WriteLine( testObj->GetAppDomainHashCode() );
}
继承层次结构
System.Object
System.MarshalByRefObject
System.Runtime.Remoting.ObjectHandle
线程安全
此类型的任何公共静态（Visual Basic 中的 Shared）成员都是线程安全的，但不保证所有实例成员都是线程安全的。
平台
Windows 98、Windows 2000 SP4、Windows Millennium Edition、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