UrlAttribute 类

定义可在调用站点上用于指定将发生激活的 URL 的属性。无法继承此类。

**命名空间:**System.Runtime.Remoting.Activation
**程序集:**mscorlib（在 mscorlib.dll 中）

语法

声明
<SerializableAttribute> _
<ComVisibleAttribute(True)> _
Public NotInheritable Class UrlAttribute
    Inherits ContextAttribute
用法
Dim instance As UrlAttribute

[SerializableAttribute] 
[ComVisibleAttribute(true)] 
public sealed class UrlAttribute : ContextAttribute

[SerializableAttribute] 
[ComVisibleAttribute(true)] 
public ref class UrlAttribute sealed : public ContextAttribute

/** @attribute SerializableAttribute() */ 
/** @attribute ComVisibleAttribute(true) */ 
public final class UrlAttribute extends ContextAttribute

SerializableAttribute 
ComVisibleAttribute(true) 
public final class UrlAttribute extends ContextAttribute

备注

当使用 CreateInstance 方法创建激活对象时，UrlAttribute 作为 Activator.CreateInstance 的参数传入激活属性数组。

有关使用属性的更多信息，请参见 利用属性扩展元数据。

示例

下面的代码示例演示如何在设置客户端激活的远程处理中使用 UrlAttribute。该示例包含三个部分：客户端、服务器和供客户端和服务器使用的远程对象。

下面的代码示例演示客户端：

using System;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Activation;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Tcp;
using System.Security.Permissions;

public class Client
{
[SecurityPermission(SecurityAction.Demand)]
    [STAThread]
    public static void Main()
    {
        // Report the initial status.
        Console.WriteLine("Starting client.");

        // Register the TCP channel.
        ChannelServices.RegisterChannel(new TcpChannel());

        // Create a url attribute object.
        UrlAttribute attribute = 
            new UrlAttribute("tcp://localhost:1234/RemoteApp");
        Console.WriteLine("UrlAttribute value: {0}", attribute.UrlValue);
        object[] activationAttributes = new object[] { attribute };

        // Register the client for the remote object.
        RemotingConfiguration.RegisterActivatedClientType(
            typeof(RemoteObject), 
            "tcp://localhost:1234/RemoteApp");

        // Activate the remote object.
        Console.WriteLine("Activating remote object.");
        RemoteObject obj = (RemoteObject) Activator.CreateInstance(
            typeof(RemoteObject), null, activationAttributes);

        // Invoke a method on the remote object.
        Console.WriteLine("Invoking Hello() on remote object.");
        obj.Hello();

        // Inform the user that the program is exiting.
        Console.WriteLine("The client is exiting.");
    }
}

#using <System.Runtime.Remoting.dll>
#using <System.dll>
#using "RemoteObject.dll"

using namespace System;
using namespace System::Runtime::Remoting;
using namespace System::Runtime::Remoting::Activation;
using namespace System::Runtime::Remoting::Channels;
using namespace System::Runtime::Remoting::Channels::Tcp;

[STAThread]
int main()
{
   
   // Report initial status.
   Console::WriteLine( "Client starting." );
   
   // Register TCP channel.
   ChannelServices::RegisterChannel( gcnew TcpChannel );
   
   // Create UrlAttribute.
   UrlAttribute^ attribute = gcnew UrlAttribute( "tcp://localhost:1234/RemoteApp" );
   Console::WriteLine( "UrlAttribute value: {0}", attribute->UrlValue );
   
   array<Object^>^activationAttributes = {attribute};
   
   // Use UrlAttribute to register for client activated remote object.
   RemotingConfiguration::RegisterActivatedClientType( RemoteObject::typeid, "tcp://localhost:1234/RemoteApp" );
   
   // Activate remote object.
   Console::WriteLine( "Activating remote object." );
   RemoteObject ^ obj = dynamic_cast<RemoteObject^>(Activator::CreateInstance( RemoteObject::typeid, nullptr, activationAttributes ));
   
   // Invoke a method on it.
   Console::WriteLine( "Invoking Hello() on remote object." );
   obj->Hello();
   
   // Inform user of termination.
   Console::WriteLine( "Terminating client." );
}

下面的代码示例演示此客户端的服务器：

using System;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Tcp;

public class Server
{
    [STAThread]
    public static void Main()
    {
        // Report the status to the user.
        Console.WriteLine("Starting server.");

        // Register the TCP channel.
        ChannelServices.RegisterChannel(new TcpChannel(1234));

        // Set the application name.
        RemotingConfiguration.ApplicationName = "RemoteApp";

        // Register the object for remoting.
        RemotingConfiguration.RegisterActivatedServiceType(
            typeof(RemoteObject));

        // Wait until the user presses ENTER.
        Console.WriteLine("Press ENTER to exit.");
        Console.ReadLine();
        Console.WriteLine("The server is exiting.");
    }
}

#using <System.Runtime.Remoting.dll>
#using <System.dll>
#using "RemoteObject.dll"

using namespace System;
using namespace System::Runtime::Remoting;
using namespace System::Runtime::Remoting::Channels;
using namespace System::Runtime::Remoting::Channels::Tcp;

[STAThread]
int main()
{
   
   // Report status to user.
   Console::WriteLine( "Server starting." );
   
   // Register the TCP channel.
   ChannelServices::RegisterChannel( gcnew TcpChannel( 1234 ) );
   
   // Set application name.
   RemotingConfiguration::ApplicationName = "RemoteApp";
   
   // Register object for client activated remoting.
   RemotingConfiguration::RegisterActivatedServiceType( RemoteObject::typeid );
   
   // Wait until termination.
   Console::WriteLine( "Press enter to end." );
   Console::ReadLine();
   Console::WriteLine( "Terminating server." );
}

下面的代码示例演示客户端和服务器使用的远程对象：

using System;
using System.Security;
using System.Security.Permissions;

public class RemoteObject : MarshalByRefObject
{
    public RemoteObject()
    {
        Console.WriteLine("You have called the constructor.");
    }

    public void Hello()
    {
        Console.WriteLine("You have called Hello().");
    }
}

using namespace System;
using namespace System::Security;
using namespace System::Security::Permissions;

[assembly:AllowPartiallyTrustedCallersAttribute];
public ref class RemoteObject: public MarshalByRefObject
{
public:
   RemoteObject()
   {
      
      // Report object construction to server's console.
      Console::WriteLine( "You have called the constructor." );
   }

   void Hello()
   {
      
      // Report method invocation to server's console.
      Console::WriteLine( "You have called Hello()." );
   }

};

继承层次结构

System.Object
   System.Attribute
     System.Runtime.Remoting.Contexts.ContextAttribute
      System.Runtime.Remoting.Activation.UrlAttribute

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

请参见

参考

UrlAttribute 成员
System.Runtime.Remoting.Activation 命名空间
ContextAttribute
IContextProperty