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Message Class

Represents the unit of communication between endpoints in a distributed environment.

Namespace:  System.ServiceModel.Channels
Assembly:  System.ServiceModel (in System.ServiceModel.dll)
public abstract class Message : IDisposable

The Message class provides a means of communicating arbitrary information between a sender and a receiver on a network. It can be used to relay information, suggest or demand a course of action, or request data.

The structure of a Message object represents a SOAP envelope. It consists of two distinct parts: the message's body and an optional collection of headers, represented by the Headers class. The message content is application-defined data sent from a sender to a receiver. The message headers enable system and application extensibility to meet the changing requirements, because you can define code to manipulate and respond to specific headers. You can also define your own headers. Message headers are serialized or deserialized along with the contents of the message.

Messages are received and sent in particular formats. Support is provided for two formats: the standard text-based XML format and a binary-based XML format. The Message object can be used to represent both SOAP 1.1 and SOAP 1.2 envelopes. Note that an instance of Message is fixed upon creation and is bound to a specific SOAP version. The Version property represents the SOAP version of the message.

A Message object can be serialized to an external store by using the WriteMessage method. Properties of the message can also be serialized, but they have to be individually identified and serialized separately. Deserializing a message to create an in-memory Message object can be done using CreateMessage. Properties must also be deserialized individually and manually added to the property collection for the specific Message instance.

The size of a Message object is fixed to the size of data it is transmitting. Every body is modeled as an instance of XmlReader, with no predefined limit on the size of the stream that the XmlReader instance is wrapping. However, specific channel providers can have a limit on the size of messages that they process.

A Message can be annotated with useful information generated by an entity that has examined and processed the message. This functionality is provided by the Headers and Properties properties. The Headers collection represents the set of SOAP headers on the message.

The Properties property represents the set of processing-level annotations on the message. Because information in headers is transmitted on the wire, an entity that examines a header must support the underlying version(s) of the protocols used by the header. However, properties provide a more version-independent way of annotating a message.

To create a Message instance, use one of the CreateMessage methods.

It is recommended that a consumer of a message always call Close when the consumer is finished accessing the contents of the message. This action frees finite system resources (for example, sockets, named pipes) that are tied to the lifetime of the message.

Special note for Managed C++ users deriving from this class:

  • Put your cleanup code in (On)(Begin)Close (and/or OnAbort), not in a destructor.

  • Avoid destructors: they cause the compiler to auto-generate IDisposable.

  • Avoid non-reference members: they can cause the compiler to auto-generate IDisposable.

  • Avoid finalizers; but if you include one, suppress the build warning and call SuppressFinalize(Object) and the finalizer itself from (On)(Begin)Close (and/or OnAbort) to emulate what would have been the auto-generated IDisposable behavior.

Notes to Inheritors:

When you inherit from Message, you must override the following members: Headers, and Version.

The following code example shows a client that uses the channel factory to send a message and read the reply.

using System;
using System.Messaging;

public class Order
{
    private int _orderId;
    private DateTime _orderTime;

    public int orderId
    {
        get
        {
            return _orderId;
        }
        set
        {
            _orderId = value;
        }
    }
    public DateTime orderTime
    {
        get
        {
            return _orderTime;
        }
        set
        {
            _orderTime = value;
        }
    }

    public Order()
    {
    }
};	

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

        try
        {
            // Create a non-transactional queue on the local computer. 
            // Note that the queue might not be immediately accessible, and 
            // therefore this example might throw an exception of type 
            // System.Messaging.MessageQueueException when trying to send a 
            // message to the newly created queue.
            CreateQueue(".\\orderQueue", false);

            // Send a message to a queue.
            processor.SendMessage();

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

            // Create a transactional queue on the local computer.
            CreateQueue(".\\orderTransQueue", true);

            // Send a message to a transactional queue.
            processor.SendMessageToTransQueue();

            // Receive a message from a transactional queue.
            processor.ReceiveMessageFromTransQueue();
        }
        catch(System.Exception e)
        {
            // Write the exception information to the console.
            Console.WriteLine(e);
        }
    }

    // Creates a new queue. 
    public static void CreateQueue(string queuePath, bool transactional)
    {
        if(!MessageQueue.Exists(queuePath))
        {
            MessageQueue.Create(queuePath, transactional);
        }
        else
        {
            Console.WriteLine(queuePath + " already exists.");
        }
    }

    // Sends an Order to a queue. 
    public void SendMessage()
    {
        // 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 queue = new MessageQueue(".\\orderQueue");

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

        // Set the message's TimeToReachQueue property to five minutes.
        orderMessage.TimeToReachQueue = TimeSpan.FromMinutes(5.0);

        // Display the new value of the message's TimeToReachQueue property.
        Console.WriteLine("Message.TimeToReachQueue: {0}",
            orderMessage.TimeToReachQueue.ToString());

        // Set the message's TimeToBeReceived property to five minutes.
        orderMessage.TimeToBeReceived = TimeSpan.FromMinutes(5.0);

        // Display the new value of the message's TimeToBeReceived property.
        Console.WriteLine("Message.TimeToBeReceived: {0}",
            orderMessage.TimeToBeReceived.ToString());

        // Set the message's UseTracing property to true.
        orderMessage.UseTracing = true;

        // Display the new value of the message's UseTracing property.
        Console.WriteLine("Message.UseTracing: {0}", orderMessage.UseTracing);

        // Set the message's Label property.
        orderMessage.Label = "Order Message";

        // Display the new value of the message's Label property.
        Console.WriteLine("Message Label: {0}", orderMessage.Label);

        // Set the message's AttachSenderId property.
        orderMessage.AttachSenderId = true;

        // Display the new value of the message's AttachSenderId property.
        Console.WriteLine("Message.AttachSenderId: {0}",
            orderMessage.AttachSenderId);

        // Set the message's Recoverable property.
        orderMessage.Recoverable = true;

        // Display the new value of the message's Recoverable property.
        Console.WriteLine("Message.Recoverable: {0}",
            orderMessage.Recoverable);

        // Set the message's ResponseQueue property. 
        // (You must have a connection to a queue.)
        orderMessage.ResponseQueue = queue;

        // Display the new value of the message's ResponseQueue property.
        Console.WriteLine("Message.ResponseQueue.QueueName: {0}",
            orderMessage.ResponseQueue.QueueName);

        // Set the message's TimeToReachQueue property to Message.InfiniteTimeout.
        orderMessage.TimeToReachQueue = Message.InfiniteTimeout;

        // Display the new value of the message's TimeToReachQueue property.
        Console.WriteLine("Message.TimeToReachQueue: {0}",
            orderMessage.TimeToReachQueue.ToString());

        // Set the message's UseDeadLetterQueue property.
        orderMessage.UseDeadLetterQueue = true;

        // Display the new value of the message's UseDeadLetterQueue property.
        Console.WriteLine("Message.UseDeadLetterQueue: {0}",
            orderMessage.UseDeadLetterQueue);

        // Set the message's UseJournalQueue property.
        orderMessage.UseJournalQueue = true;

        // Display the new value of the message's UseJournalQueue property.
        Console.WriteLine("Message.UseJournalQueue: {0}",
            orderMessage.UseJournalQueue);

        // Set the message's UseEncryption property.
        orderMessage.UseEncryption = true;

        // Display the new value of the message's UseEncryption property.
        Console.WriteLine("Message.UseEncryption: {0}",
            orderMessage.UseEncryption);

        // Send the order to the queue.
        queue.Send(orderMessage);
    }

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

        // Set the formatter to indicate the message body contains an order.
        queue.Formatter = new XmlMessageFormatter(new Type[]
            {typeof(Order)});

        // Set the queue's MessageReadPropertyFilter properties to ensure that 
        // the message includes the properties in which we are interested.
        queue.MessageReadPropertyFilter.ArrivedTime = true;
        queue.MessageReadPropertyFilter.DestinationQueue = true;
        queue.MessageReadPropertyFilter.SenderVersion = true;
        queue.MessageReadPropertyFilter.SentTime = true;
        queue.MessageReadPropertyFilter.SourceMachine = true;
        queue.MessageReadPropertyFilter.Authenticated = true;

        // Receive the message. Time out after ten seconds in case the message 
        // was not delivered.
        Message orderMessage = queue.Receive(TimeSpan.FromSeconds(10.0));

        // Format the message.
        Order sentOrder = (Order)orderMessage.Body;

        // Display message information.
        Console.WriteLine("Order ID: {0}", sentOrder.orderId.ToString());
        Console.WriteLine("Sent: {0}", sentOrder.orderTime.ToString());

        // Display the value of the message's MessageType property.
        Console.WriteLine("Message Type: {0}", orderMessage.MessageType);

        // Display the value of the message's SourceMachine property. 
        // To view this property value, the queue's 
        // MessageReadPropertyFilter.SourceMachine property must be set to 
        // true before the message is received.
        Console.WriteLine("Source Machine: {0}", orderMessage.SourceMachine);

        // Display the value of the message's DestinationQueue property. 
        // To view this property value, the queue's 
        // MessageReadPropertyFilter.DestinationQueue property must be set to 
        // true before the message is received.
        Console.WriteLine("Message.DestinationQueue.QueueName: {0}",
            orderMessage.DestinationQueue.QueueName);

        // Display the value of the message's SentTime property. 
        // To view this property value, the queue's 
        // MessageReadPropertyFilter.SentTime property must be set to 
        // true before the message is received.
        Console.WriteLine("Time sent from source queue: {0}",
            orderMessage.SentTime.ToString());

        // Display the value of the message's ArrivedTime property. 
        // To view this property value, the queue's 
        // MessageReadPropertyFilter.ArrivedTime property must be set to 
        // true before the message is received.
        Console.WriteLine("Time arrived in destination queue: {0}",
            orderMessage.ArrivedTime.ToString());

        // Display the value of the message's Authenticated property. 
        // To view this property value, the queue's 
        // MessageReadPropertyFilter.Authenticated property must be set to 
        // true before the message is received.
        Console.WriteLine("Authentication requested for this message: {0}",
            orderMessage.Authenticated.ToString());

        // Display the value of the message's SenderVersion property. 
        // To view this property value, the queue's 
        // MessageReadPropertyFilter.SenderVersion property must be set to 
        // true before the message is received.
        Console.WriteLine("Message.SenderVersion: {0}",
            orderMessage.SenderVersion);

        // Message Queuing sets this property when the message is sent. 
        // Display the value of the message's BodyType property.
        Console.WriteLine("Message.BodyType: {0}",
            orderMessage.BodyType.ToString());
    }

    // Sends an Order to a transactional queue. 
    public void SendMessageToTransQueue()
    {
        // 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 queue = new MessageQueue(".\\orderTransQueue");

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

        // Create a message queuing transaction.
        MessageQueueTransaction transaction = new MessageQueueTransaction();

        try
        {
            // Begin a transaction.
            transaction.Begin();

            // Send the order to the queue.
            queue.Send(orderMessage, transaction);

            // Commit the transaction.
            transaction.Commit();
        }
        catch (MessageQueueException e)
        {
            // Abort the transaction.
            transaction.Abort();

            // Propagate the exception. 
            throw e;
        }
        finally
        {
            // Dispose of the transaction object.
            transaction.Dispose();
        }
    }

    // Receives a message containing an order. 
    public void ReceiveMessageFromTransQueue()
    {
        Message orderMessage;

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

        // Set the formatter to indicate the message body contains an order.
        queue.Formatter = new XmlMessageFormatter(new Type[]
            {typeof(Order)});

        // Set the queue's MessageReadPropertyFilter properties to ensure that 
        // the message includes the properties in which we are interested.
        queue.MessageReadPropertyFilter.TransactionId = true;
        queue.MessageReadPropertyFilter.TransactionStatusQueue = true;
        queue.MessageReadPropertyFilter.IsFirstInTransaction = true;
        queue.MessageReadPropertyFilter.IsLastInTransaction = true;

        // Create a message queuing transaction.
        MessageQueueTransaction transaction = new MessageQueueTransaction();

        try
        {
            // Begin a transaction.
            transaction.Begin();

            // Receive the message. Time out after ten seconds in case the 
            // message was not delivered.
            orderMessage = queue.Receive(TimeSpan.FromSeconds(10.0),
                transaction);

            // Commit the transaction.
            transaction.Commit();
        }
        catch(System.Exception e)
        {
            // Abort the transaction.
            transaction.Abort();

            // Propagate the exception. 
            throw e;
        }
        finally
        {
            // Dispose of the transaction object.
            transaction.Dispose();
        }

        // Message Queuing sets this property when the message is sent. 
        // Display the value of the message's TransactionStatusQueue property. 
        // To view this property value, the queue's 
        // MessageReadPropertyFilter.TransactionStatusQueue property must be 
        // set to true before the message is received.
        Console.WriteLine("Message.TransactionStatusQueue.QueueName: {0}",
            orderMessage.TransactionStatusQueue.QueueName);

        // Display the value of the message's TransactionId property. 
        // To view this property value, the queue's 
        // MessageReadPropertyFilter.TransactionId property must be set to true 
        // before the message is received.
        Console.WriteLine("Message.TransactionId: {0}",
            orderMessage.TransactionId);

        // Display the value of the message's IsFirstInTransaction property. 
        // To view this property value, the queue's 
        // MessageReadPropertyFilter.IsFirstInTransaction property must be set 
        // to true before the message is received.
        Console.WriteLine("Message.IsFirstInTransaction: {0}",
            orderMessage.IsFirstInTransaction);

        // Display the value of the message's IsLastInTransaction property. 
        // To view this property value, the queue's 
        // MessageReadPropertyFilter.IsLastInTransaction property must be set 
        // to true before the message is received.
        Console.WriteLine("Message.IsLastInTransaction: {0}",
            orderMessage.IsLastInTransaction);
    }
}
using System;
using System.Collections.Generic;
using System.Text;
using System.ServiceModel;
using System.ServiceModel.Channels;
using System.Runtime.Serialization;

namespace ConsoleApplication1
{
    class client
    {


        static void RunClient()
        {
            //Step1: create a binding with just HTTP
            CustomBinding binding = new CustomBinding();
            binding.Elements.Add(new HttpTransportBindingElement());
            //Step2: use the binding to build the channel factory
            IChannelFactory<IRequestChannel> factory =
            binding.BuildChannelFactory<IRequestChannel>(
                             new BindingParameterCollection());
            //open the channel factory
            factory.Open();
            //Step3: use the channel factory to create a channel
            IRequestChannel channel = factory.CreateChannel(
               new EndpointAddress("http://localhost:8080/channelapp"));
            channel.Open();
            //Step4: create a message
            Message requestmessage = Message.CreateMessage(
                MessageVersion.Soap12WSAddressing10,
                "http://contoso.com/someaction",
                 "This is the body data");
            //send message
            Message replymessage = channel.Request(requestmessage);
            Console.WriteLine("Reply message received");
            Console.WriteLine("Reply action: {0}",
                                  replymessage.Headers.Action);
            string data = replymessage.GetBody<string>();
            Console.WriteLine("Reply content: {0}", data);
            //Step5: don't forget to close the message
            requestmessage.Close();
            replymessage.Close();
            //don't forget to close the channel
            channel.Close();
            //don't forget to close the factory
            factory.Close();
        }
        public static void Main()
        {
            Console.WriteLine("Press [ENTER] when service is ready");
            Console.ReadLine();
            RunClient();
            Console.WriteLine("Press [ENTER] to exit");
            Console.ReadLine();
        }
    }
}
System.Object
  System.ServiceModel.Channels.Message
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0

.NET Compact Framework

Supported in: 3.5
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