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ObjRef.ChannelInfo Property

Definition

Gets or sets the IChannelInfo for the ObjRef.

public:
 virtual property System::Runtime::Remoting::IChannelInfo ^ ChannelInfo { System::Runtime::Remoting::IChannelInfo ^ get(); void set(System::Runtime::Remoting::IChannelInfo ^ value); };
public virtual System.Runtime.Remoting.IChannelInfo ChannelInfo { get; set; }
member this.ChannelInfo : System.Runtime.Remoting.IChannelInfo with get, set
Public Overridable Property ChannelInfo As IChannelInfo

Property Value

The IChannelInfo interface for the ObjRef.

Examples

// a custom ObjRef class that outputs its status
[System::Security::Permissions::SecurityPermissionAttribute(
   System::Security::Permissions::SecurityAction::Demand,
   Flags=System::Security::Permissions::SecurityPermissionFlag::SerializationFormatter)]
[System::Security::Permissions::SecurityPermissionAttribute
(System::Security::Permissions::SecurityAction::Demand, 
Flags=System::Security::Permissions::SecurityPermissionFlag::Infrastructure)]	
[System::Security::Permissions::SecurityPermissionAttribute
(System::Security::Permissions::SecurityAction::InheritanceDemand, 
Flags=System::Security::Permissions::SecurityPermissionFlag::Infrastructure)]

public ref class MyObjRef: public ObjRef
{
private:

   // only instantiate via marshaling or deserialization
   MyObjRef(){}

public:
   MyObjRef( MarshalByRefObject^ o, Type^ t )
      : ObjRef( o, t )
   {
      Console::WriteLine( "Created MyObjRef." );
      ORDump();
   }

   MyObjRef( SerializationInfo^ i, StreamingContext c )
      : ObjRef( i, c )
   {
      Console::WriteLine( "Deserialized MyObjRef." );
   }

   virtual void GetObjectData( SerializationInfo^ s, StreamingContext c ) override
   {
      
      // After calling the base method, change the type from ObjRef to MyObjRef
      ObjRef::GetObjectData( s, c );
      s->SetType( GetType() );
      Console::WriteLine( "Serialized MyObjRef." );
   }
   
   virtual Object^ GetRealObject( StreamingContext context ) override
   {
      if ( IsFromThisAppDomain() || IsFromThisProcess() )
      {
         Console::WriteLine( "Returning actual Object* referenced by MyObjRef." );
         return ObjRef::GetRealObject( context );
      }
      else
      {
         Console::WriteLine( "Returning proxy to remote Object*." );
         return RemotingServices::Unmarshal( this );
      }
   }

   void ORDump()
   {
      Console::WriteLine( " --- Reporting MyObjRef Info --- " );
      Console::WriteLine( "Reference to {0}.", TypeInfo->TypeName );
      Console::WriteLine( "URI is {0}.", URI );
      Console::WriteLine( "\nWriting EnvoyInfo: " );
      if ( EnvoyInfo != nullptr )
      {
         IMessageSink^ EISinks = EnvoyInfo->EnvoySinks;
         while ( EISinks != nullptr )
         {
            Console::WriteLine( "\tSink: {0}", EISinks );
            EISinks = EISinks->NextSink;
         }
      }
      else
            Console::WriteLine( "\t {no sinks}" );

      Console::WriteLine( "\nWriting ChannelInfo: " );
      for ( int i = 0; i < ChannelInfo->ChannelData->Length; i++ )
         Console::WriteLine( "\tChannel: {0}", ChannelInfo->ChannelData[ i ] );
      Console::WriteLine( " ----------------------------- " );
   }
};

// a class that uses MyObjRef
public ref class LocalObject: public MarshalByRefObject
{
public:

   // overriding CreateObjRef will allow us to return a custom ObjRef
   [System::Security::Permissions::SecurityPermissionAttribute
   (System::Security::Permissions::SecurityAction::LinkDemand,
   Flags=System::Security::Permissions::SecurityPermissionFlag::Infrastructure)]
   virtual ObjRef^ CreateObjRef( Type^ t ) override
   {
      return gcnew MyObjRef( this,t );
   }
};
// a custom ObjRef class that outputs its status
public class MyObjRef : ObjRef {

   // only instantiate via marshaling or deserialization
   private MyObjRef() { }

   public MyObjRef(MarshalByRefObject o, Type t) : base(o, t) {
      Console.WriteLine("Created MyObjRef.");
      ORDump();
   }

   public MyObjRef(SerializationInfo i, StreamingContext c) : base(i, c) {
      Console.WriteLine("Deserialized MyObjRef.");
   }

   public override void GetObjectData(SerializationInfo s, StreamingContext c) {
      // After calling the base method, change the type from ObjRef to MyObjRef
      base.GetObjectData(s, c);
      s.SetType(GetType());
      Console.WriteLine("Serialized MyObjRef.");
   }

   public override Object GetRealObject(StreamingContext context) {

      if ( IsFromThisAppDomain() || IsFromThisProcess() )  {
         Console.WriteLine("Returning actual object referenced by MyObjRef.");
         return base.GetRealObject(context);
      }
      else {
         Console.WriteLine("Returning proxy to remote object.");
         return RemotingServices.Unmarshal(this);
      }
   }

   public void ORDump() {

      Console.WriteLine(" --- Reporting MyObjRef Info --- ");
      Console.WriteLine("Reference to {0}.", TypeInfo.TypeName);
      Console.WriteLine("URI is {0}.", URI);

      Console.WriteLine("\nWriting EnvoyInfo: ");

      if ( EnvoyInfo != null) {

         IMessageSink EISinks = EnvoyInfo.EnvoySinks;

         while (EISinks != null) {
            Console.WriteLine("\tSink: " + EISinks.ToString());
            EISinks = EISinks.NextSink;
         }
      }
      else
        {
            Console.WriteLine("\t {no sinks}");
        }

        Console.WriteLine("\nWriting ChannelInfo: ");
      for (int i = 0; i < ChannelInfo.ChannelData.Length; i++)
         Console.WriteLine ("\tChannel: {0}", ChannelInfo.ChannelData[i]);

      Console.WriteLine(" ----------------------------- ");
   }
}

// a class that uses MyObjRef
public class LocalObject : MarshalByRefObject  {

   // overriding CreateObjRef will allow us to return a custom ObjRef
   public override ObjRef CreateObjRef(Type t) {

      return new MyObjRef(this, t);
   }
}

Remarks

The current property holds information contributed by active channels in the process, when the ObjRef is created (see Marshal for details on marshaling). This information can be used by the channels in other processes or application domains to decide whether or not to create a transport sink to communicate with the object represented by the current instance.

Applies to

See also