Message.Formatter Proprietà

  • Riferimento

Definizione

Spazio dei nomi:
System.Messaging
Assembly:
System.Messaging.dll

Ottiene o imposta il formattatore utilizzato per serializzare o deserializzare un oggetto da e nel corpo del messaggio.

public:
 property System::Messaging::IMessageFormatter ^ Formatter { System::Messaging::IMessageFormatter ^ get(); void set(System::Messaging::IMessageFormatter ^ value); };
[System.ComponentModel.Browsable(false)]
public System.Messaging.IMessageFormatter Formatter { get; set; }
[<System.ComponentModel.Browsable(false)>]
member this.Formatter : System.Messaging.IMessageFormatter with get, set
Public Property Formatter As IMessageFormatter

Valore della proprietà

IMessageFormatter

IMessageFormatter che produce un flusso da scrivere o leggere dal corpo del messaggio. Il valore predefinito è XmlMessageFormatter.

Attributi
BrowsableAttribute

Eccezioni

ArgumentException

La proprietà Formatter è null.

Esempio

Nell'esempio di codice seguente viene illustrata la formattazione di un corpo del messaggio tramite BinaryMessageFormatter.

using System;
using System.Messaging;
using System.Drawing;
using System.IO;

namespace MyProject
{

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

        //**************************************************
        // Provides an entry point into the application.
        //		
        // This example sends and receives a message from
        // a queue.
        //**************************************************

        public static void Main()
        {
            // Create a new instance of the class.
            MyNewQueue myNewQueue = new MyNewQueue();

            // Create a queue on the local computer.
            CreateQueue(".\\myQueue");
            
            // Send a message to a queue.
            myNewQueue.SendMessage();

            // Receive a message from a queue.
            myNewQueue.ReceiveMessage();

            return;
        }

        //**************************************************
        // Creates a new queue.
        //**************************************************

        public static void CreateQueue(string queuePath)
        {
            try	
            {
                if(!MessageQueue.Exists(queuePath))
                {
                    MessageQueue.Create(queuePath);
                }
                else
                {
                    Console.WriteLine(queuePath + " already exists.");
                }
            }
            catch (MessageQueueException e)
            {
                Console.WriteLine(e.Message);
            }
        }

        //**************************************************
        // Sends an image to a queue, using the BinaryMessageFormatter.
        //**************************************************
        
        public 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 = new MessageQueue(".\\myQueue");
                
                Message myMessage = new Message(myImage, new BinaryMessageFormatter());

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

            return;
        }

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

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

                // Set the formatter to indicate body contains an Order.
                myQueue.Formatter = new BinaryMessageFormatter();

                // Receive and format the message.
                System.Messaging.Message myMessage = myQueue.Receive();
                Bitmap myImage = (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;
        }
    }
}

Imports System.Messaging
Imports System.Drawing
Imports System.IO


Namespace MyProj
    _
   
   
   Public Class MyNewQueue
      
      
      '**************************************************
      ' Provides an entry point into the application.
      '		 
      ' This example sends and receives a message from
      ' a queue.
      '**************************************************
      Public Shared Sub Main()
         ' Create a new instance of the class.
         Dim myNewQueue As New MyNewQueue()
         
         ' Create a queue on the local computer.
         CreateQueue(".\myQueue")
         
         ' Send a message to a queue.
         myNewQueue.SendMessage()
         
         ' Receive a message from a queue.
         myNewQueue.ReceiveMessage()
         
         Return
      End Sub
      
      
      '**************************************************
      ' Creates a new queue.
      '**************************************************
      Public Shared Sub CreateQueue(queuePath As String)
         Try
            If Not MessageQueue.Exists(queuePath) Then
               MessageQueue.Create(queuePath)
            Else
               Console.WriteLine((queuePath + " already exists."))
            End If
         Catch e As MessageQueueException
            Console.WriteLine(e.Message)
         End Try
      End Sub
       
      
      '**************************************************
      ' Sends an image to a queue, using the BinaryMessageFormatter.
      '**************************************************
      Public Sub 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.
            Dim myImage As Image = Bitmap.FromFile("SentImage.bmp")
            
            ' Connect to a queue on the local computer.
            Dim myQueue As New MessageQueue(".\myQueue")
            
            Dim myMessage As New Message(myImage, New BinaryMessageFormatter())
            
            ' Send the image to the queue.
            myQueue.Send(myMessage)
         Catch e As ArgumentException
            Console.WriteLine(e.Message)
         End Try 
         
         Return
      End Sub
      
      
      
      '**************************************************
      ' Receives a message containing an image.
      '**************************************************
      Public Sub ReceiveMessage()
         
         Try
            
            ' Connect to the a queue on the local computer.
            Dim myQueue As New MessageQueue(".\myQueue")
            
            ' Set the formatter to indicate body contains an Order.
            myQueue.Formatter = New BinaryMessageFormatter()
            
            ' Receive and format the message. 
            Dim myMessage As System.Messaging.Message = myQueue.Receive()
            Dim myImage As Bitmap = CType(myMessage.Body, Bitmap)
            
            ' This will be saved in the \bin\debug or \bin\retail folder.
            myImage.Save("ReceivedImage.bmp", System.Drawing.Imaging.ImageFormat.Bmp)
         
         
         
         'Catch
         ' Handle Message Queuing exceptions.
         
         ' Handle invalid serialization format.
         Catch e As InvalidOperationException
            Console.WriteLine(e.Message)
         
         Catch e As IOException
         End Try
         ' Handle file access exceptions.
         
         ' Catch other exceptions as necessary.
         Return
      End Sub
   End Class
End Namespace 'MyProj

Nell'esempio di codice seguente viene illustrata la formattazione di un corpo del messaggio tramite 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;
}

using System;
using System.Messaging;
using System.Drawing;
using System.IO;

namespace MyProject
{

    // The following example
    // sends to a queue and receives from a queue.
    public class Order
    {
        public int orderId;
        public DateTime orderTime;
    };	

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

        //**************************************************
        // Provides an entry point into the application.
        //		
        // This example sends and receives a message from
        // a queue.
        //**************************************************

        public static void Main()
        {
            // Create a new instance of the class.
            MyNewQueue myNewQueue = new MyNewQueue();

            // Create a queue on the local computer.
            CreateQueue(".\\myQueue");
            
            // Send a message to a queue.
            myNewQueue.SendMessage();

            // Receive a message from a queue.
            myNewQueue.ReceiveMessage();

            return;
        }

        //**************************************************
        // Creates a new queue.
        //**************************************************

        public static void CreateQueue(string queuePath)
        {
            try	
            {
                if(!MessageQueue.Exists(queuePath))
                {
                    MessageQueue.Create(queuePath);
                }
                else
                {
                    Console.WriteLine(queuePath + " already exists.");
                }
            }
            catch (MessageQueueException e)
            {
                Console.WriteLine(e.Message);
            }
        }

        //**************************************************
        // Sends an Order to a queue.
        //**************************************************
        
        public void SendMessage()
        {
            try
            {

                // Create a new order and set values.
                Order sentOrder = new Order();
                sentOrder.orderId = 3;
                sentOrder.orderTime = DateTime.Now;

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

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

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

            return;
        }

        //**************************************************
        // Receives a message containing an order.
        //**************************************************
        
        public  void ReceiveMessage()
        {
            // Connect to the a queue on the local computer.
            MessageQueue myQueue = new MessageQueue(".\\myQueue");

            // Set the formatter to indicate body contains an Order.
            myQueue.Formatter = new XmlMessageFormatter(new Type[]
                {typeof(MyProject.Order)});
            
            try
            {
                // Receive and format the message.
                Message myMessage =	myQueue.Receive();
                Order myOrder = (Order)myMessage.Body;

                // Display message information.
                Console.WriteLine("Order ID: " +
                    myOrder.orderId.ToString());
                Console.WriteLine("Sent: " +
                    myOrder.orderTime.ToString());
            }
            
            catch (MessageQueueException)
            {
                // Handle Message Queuing exceptions.
            }

                // Handle invalid serialization format.
            catch (InvalidOperationException e)
            {
                Console.WriteLine(e.Message);
            }
            
            // Catch other exceptions as necessary.

            return;
        }
    }
}

Imports System.Messaging
Imports System.Drawing
Imports System.IO



   
' The following example 
' sends to a queue and receives from a queue.
Public Class Order
      Public orderId As Integer
      Public orderTime As DateTime
End Class

   
  
' Provides a container class for the example.

Public Class MyNewQueue
      
      

   ' Provides an entry point into the application.
   '		 
   ' This example sends and receives a message from
   ' a queue.

   Public Shared Sub Main()
      ' Create a new instance of the class.
      Dim myNewQueue As New MyNewQueue()
        
      ' Create a queue on the local computer.
      CreateQueue(".\myQueue")
         
      ' Send a message to a queue.
      myNewQueue.SendMessage()
       
      ' Receive a message from a queue.
      myNewQueue.ReceiveMessage()
         
      Return
   End Sub
      
      

      ' Creates a new queue.
   Public Shared Sub CreateQueue(queuePath As String)
      Try
         If Not MessageQueue.Exists(queuePath) Then
            MessageQueue.Create(queuePath)
         Else
            Console.WriteLine((queuePath + " already exists."))
         End If
      Catch e As MessageQueueException
         Console.WriteLine(e.Message)
      End Try
   End Sub
       
      

      ' Sends an Order to a queue.

   Public Sub SendMessage()
      Try
            
            ' Create a new order and set values.
            Dim sentOrder As New Order()
            sentOrder.orderId = 3
            sentOrder.orderTime = DateTime.Now
            
            ' Connect to a queue on the local computer.
            Dim myQueue As New MessageQueue(".\myQueue")
            
            
            
            ' Create the new order.
            Dim myMessage As New Message(sentOrder)
            
            ' Send the order to the queue.
            myQueue.Send(myMessage)
      Catch e As ArgumentException
            Console.WriteLine(e.Message)
      End Try 
         
      Return
   End Sub
      
      
      
 
      ' Receives a message containing an order.
 
   Public Sub ReceiveMessage()
         ' Connect to the a queue on the local computer.
         Dim myQueue As New MessageQueue(".\myQueue")
         
         ' Set the formatter to indicate body contains an Order.
         myQueue.Formatter = New XmlMessageFormatter(New Type() {GetType(Order)})
         
         Try
            ' Receive and format the message. 
            Dim myMessage As Message = myQueue.Receive()
            Dim myOrder As Order = CType(myMessage.Body, Order)
            
            ' Display message information.
            Console.WriteLine(("Order ID: " + myOrder.orderId.ToString()))
            Console.WriteLine(("Sent: " + myOrder.orderTime.ToString()))
         
  
         ' Handle invalid serialization format.
         Catch e As InvalidOperationException
            Console.WriteLine(e.Message)
         End Try
         
         ' Catch other exceptions as necessary.
         Return
   End Sub
End Class

Commenti

Utilizzare la proprietà durante la lettura e la Formatter scrittura di un messaggio. Quando un messaggio viene inviato alla coda, il formattatore serializza la Body proprietà in un flusso che può essere inviato alla coda dei messaggi. Durante la lettura da una coda, il formattatore deserializza i dati del messaggio nella Body proprietà .

A meno che non si scriva il contenuto del messaggio direttamente nella BodyStream proprietà , impostare la Formatter proprietà prima di inviare il messaggio. Quando il Send metodo viene chiamato nell'istanza MessageQueue , il corpo viene serializzato usando il formattatore contenuto nella Formatter proprietà . Se si invia il messaggio senza specificare un valore per la proprietà, per impostazione Formatter predefinita il formattatore è XmlMessageFormatter.

L'oggetto XmlMessageFormatter è ad accoppiamento libero, pertanto non è necessario avere lo stesso tipo di oggetto nel mittente e nel ricevitore quando si usa questo formato. Oggetto ActiveXMessageFormatter e BinaryMessageFormatter serializzare i dati in rappresentazione binaria. Viene utilizzato durante l'invio ActiveXMessageFormatter o la ricezione di componenti COM.

Si applica a

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