IMessageSink Gränssnitt

Definition

public interface class IMessageSink

public interface IMessageSink

[System.Runtime.InteropServices.ComVisible(true)]
public interface IMessageSink

type IMessageSink = interface

[<System.Runtime.InteropServices.ComVisible(true)>]
type IMessageSink = interface

Public Interface IMessageSink

Härledda

System.Runtime.Remoting.Channels.BinaryClientFormatterSink

System.Runtime.Remoting.Channels.IClientFormatterSink

System.Runtime.Remoting.Channels.SoapClientFormatterSink

System.Runtime.Remoting.Messaging.AsyncResult

Attribut

ComVisibleAttribute

Exempel

I följande kodexempel visas implementeringen av IMessageSink gränssnittet. Observera att exemplet förutsätter typdefinitioner och sammansättningsreferenser som måste anges för att exemplet ska kompileras.

#using <System.Runtime.Remoting.dll>
#using <System.dll>
#using <IMessageSink_Share.dll>

using namespace System;
using namespace System::Collections;
using namespace System::Threading;
using namespace System::Runtime::Remoting;
using namespace System::Runtime::Remoting::Channels;
using namespace System::Runtime::Remoting::Channels::Http;
using namespace System::Runtime::Remoting::Proxies;
using namespace System::Runtime::Remoting::Messaging;
using namespace System::Security::Permissions;
using namespace Share;

public ref class MyProxy: public RealProxy
{
private:
   String^ myUrl;
   String^ myObjectURI;
   IMessageSink^ myMessageSink;

public:
    [System::Security::Permissions::PermissionSetAttribute(System::Security::Permissions::SecurityAction::LinkDemand)]

   MyProxy( Type^ myType, String^ myUrl1 )
      : RealProxy( myType )
   {
      myUrl = myUrl1;
      array<IChannel^>^myRegisteredChannels = ChannelServices::RegisteredChannels;
      IEnumerator^ myEnum = myRegisteredChannels->GetEnumerator();
      while ( myEnum->MoveNext() )
      {
         IChannel^ channel = safe_cast<IChannel^>(myEnum->Current);
         if ( dynamic_cast<IChannelSender^>(channel) )
         {
            IChannelSender^ myChannelSender = dynamic_cast<IChannelSender^>(channel);
            myMessageSink = myChannelSender->CreateMessageSink( myUrl, nullptr, myObjectURI );
            if ( myMessageSink != nullptr )
                        break;
         }
      }

      if ( myMessageSink == nullptr )
      {
         throw gcnew Exception( String::Format( "A supported channel could not be found for myUrl1:{0}", myUrl ) );
      }
   }

   virtual IMessage^ Invoke( IMessage^ myMesg ) override
   {
      Console::WriteLine( "MyProxy.Invoke Start" );
      if ( dynamic_cast<IMethodCallMessage^>(myMesg) )
            Console::WriteLine( "IMethodCallMessage" );

      if ( dynamic_cast<IMethodReturnMessage^>(myMesg) )
            Console::WriteLine( "IMethodReturnMessage" );

      
      Console::WriteLine( "Message Properties" );
      IDictionary^ myDictionary = myMesg->Properties;
      IDictionaryEnumerator^ myEnum = dynamic_cast<IDictionaryEnumerator^>(myDictionary->GetEnumerator());
      while ( myEnum->MoveNext() )
      {
         Object^ myKey = myEnum->Key;
         String^ myKeyName = myKey->ToString();
         Object^ myValue = myEnum->Value;
         Console::WriteLine( "{0} : {1}", myKeyName, myEnum->Value );
         if ( myKeyName->Equals( "__Args" ) )
         {
            array<Object^>^myArgs = (array<Object^>^)myValue;
            for ( int myInt = 0; myInt < myArgs->Length; myInt++ )
               Console::WriteLine( "arg: {0} myValue: {1}", myInt, myArgs[ myInt ] );
         }

         if ( (myKeyName->Equals( "__MethodSignature" )) && (nullptr != myValue) )
         {
            array<Object^>^myArgs = (array<Object^>^)myValue;
            for ( int myInt = 0; myInt < myArgs->Length; myInt++ )
               Console::WriteLine( "arg: {0} myValue: {1}", myInt, myArgs[ myInt ] );
         }
      }

      Console::WriteLine( "myUrl1 {0} object URI{1}", myUrl, myObjectURI );
      myDictionary->default[ "__Uri" ] = myUrl;
      Console::WriteLine( "URI {0}", myDictionary->default[ "__URI" ] );
      
      IMessage^ myRetMsg = myMessageSink->SyncProcessMessage( myMesg );
      if ( dynamic_cast<IMethodReturnMessage^>(myRetMsg) )
      {
         IMethodReturnMessage^ myMethodReturnMessage = dynamic_cast<IMethodReturnMessage^>(myRetMsg);
      }

      
      Console::WriteLine( "MyProxy.Invoke - Finish" );
      return myRetMsg;
   }

};


//
// Main function that drives the whole sample
//
int main()
{
   ChannelServices::RegisterChannel( gcnew HttpChannel, false );
   Console::WriteLine( "Remoting Sample:" );
   Console::WriteLine( "Generate a new MyProxy using the Type" );
   Type^ myType = MyHelloService::typeid;
   String^ myUrl1 = "http://localhost/myServiceAccess.soap";
   MyProxy^ myProxy = gcnew MyProxy( myType,myUrl1 );
   Console::WriteLine( "Obtain the transparent proxy from myProxy" );
   MyHelloService^ myService = dynamic_cast<MyHelloService^>(myProxy->GetTransparentProxy());
   Console::WriteLine( "Calling the Proxy" );
   String^ myReturnString = myService->myFunction( "bill" );
   Console::WriteLine( "Checking result : {0}", myReturnString );
   if ( myReturnString->Equals( "Hi there bill, you are using .NET Remoting" ) )
   {
      Console::WriteLine( "myService.HelloMethod PASSED : returned {0}", myReturnString );
   }
   else
   {
      Console::WriteLine( "myService.HelloMethod FAILED : returned {0}", myReturnString );
   }
}

using System;
using System.Collections;
using System.Threading;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Http;
using System.Runtime.Remoting.Proxies;
using System.Runtime.Remoting.Messaging;
using Share;	

namespace MyNameSpace
{

   public class MyProxy : RealProxy
   {
      string myUrl;
      string myObjectURI;
      IMessageSink myMessageSink;

      public MyProxy(Type myType, string myUrl1)
         : base(myType)
      {

         myUrl = myUrl1;

         IChannel[] myRegisteredChannels = ChannelServices.RegisteredChannels;
         foreach (IChannel channel in myRegisteredChannels )
         {
            if (channel is IChannelSender)
            {
               IChannelSender myChannelSender = (IChannelSender)channel;

               myMessageSink = myChannelSender.CreateMessageSink(myUrl, null, out myObjectURI);
               if (myMessageSink != null)
                  break;
            }
         }

         if (myMessageSink == null)
         {
            throw new Exception("A supported channel could not be found for myUrl1:"+ myUrl);
         }
      }

      public override IMessage Invoke(IMessage myMesg)
      {
         Console.WriteLine("MyProxy.Invoke Start");

         if (myMesg is IMethodCallMessage)
            Console.WriteLine("IMethodCallMessage");

         if (myMesg is IMethodReturnMessage)
            Console.WriteLine("IMethodReturnMessage");

         Console.WriteLine("Message Properties");
         IDictionary myDictionary = myMesg.Properties;
         IDictionaryEnumerator myEnum = (IDictionaryEnumerator) myDictionary.GetEnumerator();

         while (myEnum.MoveNext())
         {
            object myKey = myEnum.Key;
            string myKeyName = myKey.ToString();
            object myValue = myEnum.Value;

            Console.WriteLine("{0} : {1}", myKeyName, myEnum.Value);
            if (myKeyName == "__Args")
            {
               object[] myArgs = (object[])myValue;
               for (int myInt = 0; myInt < myArgs.Length; myInt++)
                  Console.WriteLine("arg: {0} myValue: {1}", myInt, myArgs[myInt]);
            }

            if ((myKeyName == "__MethodSignature") && (null != myValue))
            {
               object[] myArgs = (object[])myValue;
               for (int myInt = 0; myInt < myArgs.Length; myInt++)
                  Console.WriteLine("arg: {0} myValue: {1}", myInt, myArgs[myInt]);
            }
         }

         Console.WriteLine("myUrl1 {0} object URI{1}",myUrl,myObjectURI);

         myDictionary["__Uri"] = myUrl;
         Console.WriteLine("URI {0}", myDictionary["__URI"]);
         IMessage myRetMsg = myMessageSink.SyncProcessMessage(myMesg);

         if (myRetMsg is IMethodReturnMessage)
         {
            IMethodReturnMessage myMethodReturnMessage = (IMethodReturnMessage)myRetMsg;
         }

         Console.WriteLine("MyProxy.Invoke - Finish");
         return myRetMsg;
      }
   }

   //
   // Main class that drives the whole sample
   //
   public class ProxySample
   {
      public static void Main()
      {
         ChannelServices.RegisterChannel(new HttpChannel());

         Console.WriteLine("Remoting Sample:");

         Console.WriteLine("Generate a new MyProxy using the Type");
         Type myType = typeof(MyHelloService);
         string myUrl1 = "http://localhost/myServiceAccess.soap";
         MyProxy myProxy = new MyProxy(myType, myUrl1);

         Console.WriteLine("Obtain the transparent proxy from myProxy");
         MyHelloService myService = (MyHelloService)myProxy.GetTransparentProxy();

         Console.WriteLine("Calling the Proxy");
         string myReturnString = myService.myFunction("bill");

         Console.WriteLine("Checking result : {0}", myReturnString);

         if (myReturnString == "Hi there bill, you are using .NET Remoting")
         {
            Console.WriteLine("myService.HelloMethod PASSED : returned {0}", myReturnString);
         }
         else
         {
            Console.WriteLine("myService.HelloMethod FAILED : returned {0}", myReturnString);
         }
      }
   }
}

Imports System.Collections
Imports System.Threading
Imports System.Runtime.Remoting
Imports System.Runtime.Remoting.Channels
Imports System.Runtime.Remoting.Channels.Http
Imports System.Runtime.Remoting.Proxies
Imports System.Runtime.Remoting.Messaging
Imports System.Security.Permissions
Imports Share


Namespace MyNameSpace

   Public Class MyProxy
      Inherits RealProxy
      Private myUrl As String
      Private myObjectURI As String
      Private myMessageSink As IMessageSink

      <PermissionSet(SecurityAction.LinkDemand)> _
      Public Sub New(myType As Type, myUrl1 As String)
         MyBase.New(myType)

         myUrl = myUrl1

         Dim myRegisteredChannels As IChannel() = ChannelServices.RegisteredChannels

         Dim channel As IChannel
         For Each channel In  myRegisteredChannels
            If TypeOf channel Is IChannelSender Then
               Dim myChannelSender As IChannelSender = CType(channel, IChannelSender)

               myMessageSink = myChannelSender.CreateMessageSink(myUrl, Nothing, myObjectURI)
               If Not (myMessageSink Is Nothing) Then
                  Exit For
               End If
            End If
         Next channel
         If myMessageSink Is Nothing Then
            Throw New Exception("A supported channel could not be found for myUrl1:" + myUrl)
         End If
      End Sub

      <SecurityPermission(SecurityAction.LinkDemand, Flags := SecurityPermissionFlag.Infrastructure)> _
      Public Overrides Function Invoke(ByVal myMesg As IMessage) As IMessage
         Console.WriteLine("MyProxy.Invoke Start")

         If TypeOf myMesg Is IMethodCallMessage Then
            Console.WriteLine("IMethodCallMessage")
         End If
         If TypeOf myMesg Is IMethodReturnMessage Then
            Console.WriteLine("IMethodReturnMessage")
         End If

         Console.WriteLine("Message Properties")
         Dim myDictionary As IDictionary = myMesg.Properties
         Dim myEnum As IDictionaryEnumerator = CType(myDictionary.GetEnumerator(), IDictionaryEnumerator)

         While myEnum.MoveNext()
            Dim myKey As Object = myEnum.Key
            Dim myKeyName As String = myKey.ToString()
            Dim myValue As Object = myEnum.Value

            Console.WriteLine( "{0} : {1}", myKeyName, myEnum.Value)
            If myKeyName = "__Args" Then
               Dim myArgs As Object() = CType(myValue, Object())
               Dim myInt As Integer
               For myInt = 0 To myArgs.Length - 1
                  Console.WriteLine(  "arg: {0} myValue: {1}", myInt, myArgs(myInt))
               Next myInt
            End If
            If myKeyName = "__MethodSignature" And Not (myValue Is Nothing) Then
               Dim myArgs As Object() = CType(myValue, Object())
               Dim myInt As Integer
               For myInt = 0 To myArgs.Length - 1
                  Console.WriteLine("arg: {0} myValue: {1}", myInt, myArgs(myInt))
               Next myInt
            End If
         End While

         Console.WriteLine("myUrl1 {0} object URI{1}", myUrl, myObjectURI)

         myDictionary("__Uri") = myUrl
         Console.WriteLine("URI {0}", myDictionary("__URI"))

         Dim myRetMsg As IMessage = myMessageSink.SyncProcessMessage(myMesg)

         If TypeOf (myRetMsg) Is IMethodReturnMessage Then
            Dim myMethodReturnMessage As IMethodReturnMessage = CType(myRetMsg, IMethodReturnMessage)
         End If

         Console.WriteLine("MyProxy.Invoke - Finish")
         Return myRetMsg
      End Function 'Invoke
   End Class

   '
   ' Main class that drives the whole sample
   '
   Public Class ProxySample
      <PermissionSet(SecurityAction.LinkDemand)> _
      Public Shared Sub Main()
         ChannelServices.RegisterChannel(New HttpChannel())

         Console.WriteLine("Remoting Sample:")

         Console.WriteLine("Generate a new MyProxy using the Type")
         Dim myType As Type = GetType(MyHelloService)
         Dim myUrl1 As String = "http://localhost/myServiceAccess.soap"
         Dim myProxy As New MyProxy(myType, myUrl1)

         Console.WriteLine("Obtain the transparent proxy from myProxy")
         Dim myService As MyHelloService = CType(myProxy.GetTransparentProxy(), MyHelloService)

         Console.WriteLine("Calling the Proxy")
         Dim myReturnString As String = myService.myFunction("bill")

         Console.WriteLine("Checking result : {0}", myReturnString)

         If myReturnString = "Hi there bill, you are using .NET Remoting" Then
            Console.WriteLine("myService.HelloMethod PASSED : returned {0}", myReturnString)
         Else
            Console.WriteLine("myService.HelloMethod FAILED : returned {0}", myReturnString)
         End If
      End Sub
   End Class
End Namespace 'MyNameSpace

Kommentarer

När ett metodanrop görs på proxyn ger fjärrkommunikationsinfrastrukturen det stöd som krävs för att skicka argumenten till det faktiska objektet över fjärrkommunikationsgränserna, anropa den faktiska objektmetoden med argumenten och returnera resultatet tillbaka till klienten för proxyobjektet.

Ett fjärrmetodanrop är ett meddelande som går från klientdelen till serverdelen och eventuellt tillbaka igen. När fjärrmetodanropet korsar fjärrkommunikationsgränser på vägen passerar det genom en kedja av IMessageSink objekt. Varje mottagare i kedjan tar emot meddelandeobjektet, utför en specifik åtgärd och delegerar till nästa mottagare i kedjan. Proxyobjektet innehåller en referens till det första IMessageSink objektet som måste användas för att starta kedjan.

För asynkrona anrop tillhandahåller varje mottagare vid tidpunkten för delegering en svarsmottagare (en annan IMessageSink) som anropas av nästa mottagare när svaret är på väg tillbaka.

Olika typer av mottagare utför olika åtgärder, beroende på vilken typ av meddelandeobjekt som tas emot. Till exempel kan en mottagare orsaka att ett lås tas, en annan kan framtvinga anropssäkerhet, en annan kan utföra flödesanropskontroll och tillförlitlighetstjänster och ytterligare en annan kan transportera anropet till en annan AppDomain, process eller dator. Två eller flera meddelandemottagare i kedjan kan interagera med varandra när det gäller varje specifik åtgärd.

Anteckningar till implementerare

Det är viktigt att observera att kod som implementerar det aktuella gränssnittet måste tillhandahålla implementeringar för både SyncProcessMessage(IMessage) och AsyncProcessMessage(IMessage, IMessageSink), eftersom synkrona anrop kan konverteras till asynkrona anrop och vice versa. Båda metoderna måste implementeras, även om mottagaren inte stöder asynkron bearbetning.