Message::Formatter Property

 

Gets or sets the formatter used to serialize an object into or deserialize an object from the message body.

Namespace:   System.Messaging
Assembly:  System.Messaging (in System.Messaging.dll)

public:
[BrowsableAttribute(false)]
property IMessageFormatter^ Formatter {
	IMessageFormatter^ get();
	void set(IMessageFormatter^ value);
}

Property Value

Type: System.Messaging::IMessageFormatter^

The IMessageFormatter that produces a stream to be written to or read from the message body. The default is XmlMessageFormatter.

Exception Condition
ArgumentException

The Formatter property is null.

Use the Formatter property when reading and writing a message. When a message is sent to the queue, the formatter serializes the Body property into a stream that can be sent to the message queue. When reading from a queue, the formatter deserializes the message data into the Body property.

Unless you write the contents of the message directly to the BodyStream property, set the Formatter property before you send the message. When the Send method is called on the MessageQueue instance, the body is serialized using the formatter contained in the Formatter property. If you send the message without specifying a value for the Formatter property, the formatter defaults to XmlMessageFormatter.

The XmlMessageFormatter is loosely coupled, so it is not necessary to have the same object type on the sender and receiver when using this format. The ActiveXMessageFormatter and BinaryMessageFormatter serialize the data into binary representation. The ActiveXMessageFormatter is used when sending or receiving COM components.

The following code example demonstrates formatting a message body using BinaryMessageFormatter.

#using <system.dll>
#using <system.messaging.dll>
#using <system.drawing.dll>

using namespace System;
using namespace System::Messaging;
using namespace System::Drawing;
using namespace System::IO;

/// <summary>
/// Provides a container class for the example.
/// </summary>
ref class MyNewQueue
{
public:

   //*************************************************
   // Creates a new queue.
   //*************************************************
   static void CreateQueue( String^ queuePath )
   {
      try
      {
         if (  !MessageQueue::Exists( queuePath ) )
         {
            MessageQueue::Create( queuePath );
         }
         else
         {
            Console::WriteLine(  "{0} already exists.", queuePath );
         }
      }
      catch ( MessageQueueException^ e ) 
      {
         Console::WriteLine( e->Message );
      }

   }


   //*************************************************
   // Sends an image to a queue, using the BinaryMessageFormatter.
   //*************************************************
   void SendMessage()
   {
      try
      {

         // Create a new bitmap.
         // The file must be in the \bin\debug or \bin\retail folder, or
         // you must give a full path to its location.
         Image^ myImage = Bitmap::FromFile( "SentImage::bmp" );

         // Connect to a queue on the local computer.
         MessageQueue^ myQueue = gcnew MessageQueue( ".\\myQueue" );
         Message^ myMessage = gcnew Message( myImage,gcnew BinaryMessageFormatter );

         // Send the image to the queue.
         myQueue->Send( myMessage );
      }
      catch ( ArgumentException^ e ) 
      {
         Console::WriteLine( e->Message );
      }

      return;
   }


   //*************************************************
   // Receives a message containing an image.
   //*************************************************
   void ReceiveMessage()
   {
      try
      {

         // Connect to the a queue on the local computer.
         MessageQueue^ myQueue = gcnew MessageQueue( ".\\myQueue" );

         // Set the formatter to indicate body contains an Order.
         myQueue->Formatter = gcnew BinaryMessageFormatter;

         // Receive and format the message. 
         Message^ myMessage = myQueue->Receive();
         Bitmap^ myImage = static_cast<Bitmap^>(myMessage->Body);

         // This will be saved in the \bin\debug or \bin\retail folder.
         myImage->Save( "ReceivedImage::bmp", System::Drawing::Imaging::ImageFormat::Bmp );
      }
      catch ( MessageQueueException^ ) 
      {

         // Handle Message Queuing exceptions.
      }
      // Handle invalid serialization format.
      catch ( InvalidOperationException^ e ) 
      {
         Console::WriteLine( e->Message );
      }
      catch ( IOException^ e ) 
      {

         // Handle file access exceptions.
      }


      // Catch other exceptions as necessary.
      return;
   }

};


//*************************************************
// Provides an entry point into the application.
//         
// This example sends and receives a message from
// a queue.
//*************************************************
int main()
{

   // Create a new instance of the class.
   MyNewQueue^ myNewQueue = gcnew MyNewQueue;

   // Create a queue on the local computer.
   MyNewQueue::CreateQueue( ".\\myQueue" );

   // Send a message to a queue.
   myNewQueue->SendMessage();

   // Receive a message from a queue.
   myNewQueue->ReceiveMessage();
   return 0;
}

The following code example demonstrates formatting a message body using XmlMessageFormatter.

#using <system.dll>
#using <system.messaging.dll>
#using <system.drawing.dll>

using namespace System;
using namespace System::Messaging;
using namespace System::Drawing;
using namespace System::IO;
ref class Order
{
public:
   int orderId;
   DateTime orderTime;
};

ref class MyNewQueue
{
public:
   static void CreateQueue( String^ queuePath )
   {
      try
      {
         if (  !MessageQueue::Exists( queuePath ) )
         {
            MessageQueue::Create( queuePath );
         }
         else
         {
            Console::WriteLine(  "{0} already exists.", queuePath );
         }
      }
      catch ( MessageQueueException^ e ) 
      {
         Console::WriteLine( e->Message );
      }

   }

   void SendMessage()
   {
      try
      {
         // Create a new order and set values.
         Order^ sentOrder = gcnew Order;
         sentOrder->orderId = 3;
         sentOrder->orderTime = DateTime::Now;

         // Connect to a queue on the local computer.
         MessageQueue^ myQueue = gcnew MessageQueue( ".\\myQueue" );

         // Create the new order.
         Message^ myMessage = gcnew Message( sentOrder );

         // Send the order to the queue.
         myQueue->Send( myMessage );
      }
      catch ( ArgumentException^ e ) 
      {
         Console::WriteLine( e->Message );
      }

      return;
   }

   void ReceiveMessage()
   {
      // Connect to the a queue on the local computer.
      MessageQueue^ myQueue = gcnew MessageQueue( ".\\myQueue" );

      // Set the formatter to indicate body contains an Order.
      array<Type^>^p = gcnew array<Type^>(1);
      p[ 0 ] = Order::typeid;
      myQueue->Formatter = gcnew XmlMessageFormatter( p );
      try
      {
         // Receive and format the message. 
         Message^ myMessage = myQueue->Receive();
         Order^ myOrder = dynamic_cast<Order^>(myMessage->Body);

         // Display message information.
         Console::WriteLine( "Order ID: {0}", myOrder->orderId );
         Console::WriteLine( "Sent: {0}", myOrder->orderTime );
      }
      catch ( MessageQueueException^ ) 
      {
         // Handle Message Queuing exceptions.
      }
      // Handle invalid serialization format.
      catch ( InvalidOperationException^ e ) 
      {
         Console::WriteLine( e->Message );
      }

      // Catch other exceptions as necessary.
      return;
   }
};

int main()
{
   // Create a new instance of the class.
   MyNewQueue^ myNewQueue = gcnew MyNewQueue;

   // Create a queue on the local computer.
   MyNewQueue::CreateQueue( ".\\myQueue" );

   // Send a message to a queue.
   myNewQueue->SendMessage();

   // Receive a message from a queue.
   myNewQueue->ReceiveMessage();
   return 0;
}

.NET Framework
Available since 1.1
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