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Message Class

Provides access to the properties needed to define a Message Queuing message.

System.Object
  System.MarshalByRefObject
    System.ComponentModel.Component
      System.Messaging.Message

Namespace:  System.Messaging
Assembly:  System.Messaging (in System.Messaging.dll)
public class Message : Component

The Message type exposes the following members.

  Name Description
Public method Message() Initializes a new instance of the Message class with an empty body.
Public method Message(Object) Initializes a new instance of the Message class, using the XmlMessageFormatter to serialize the specified object into the body of the message.
Public method Message(Object, IMessageFormatter) Initializes a new instance of the Message class using the specified formatter to serialize the specified object into the body of the message.
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  Name Description
Public property AcknowledgeType Gets or sets the type of acknowledgment message to be returned to the sending application.
Public property Acknowledgment Gets the classification of acknowledgment that this message represents.
Public property AdministrationQueue Gets or sets the queue that receives the acknowledgement messages that Message Queuing generates.
Public property AppSpecific Gets or sets additional, application-specific information.
Public property ArrivedTime Gets the time that the message arrived in the destination queue.
Public property AttachSenderId Gets or sets a value that indicates whether the sender ID should be attached to the message.
Public property Authenticated Gets a value that indicates whether the message was authenticated.
Public property AuthenticationProviderName Gets or sets the name of the cryptographic provider used to generate the digital signature of the message.
Public property AuthenticationProviderType Gets or sets the type of cryptographic provider used to generate the digital signature of the message.
Public property Body Gets or sets the content of the message.
Public property BodyStream Gets or sets the information in the body of the message.
Public property BodyType Gets or sets the type of data that the message body contains.
Protected property CanRaiseEvents Gets a value indicating whether the component can raise an event. (Inherited from Component.)
Public property ConnectorType Gets or sets a value that indicates that some message properties typically set by Message Queuing were set by the sending application.
Public property Container Gets the IContainer that contains the Component. (Inherited from Component.)
Public property CorrelationId Gets or sets the message identifier used by acknowledgment, report, and response messages to reference the original message.
Protected property DesignMode Gets a value that indicates whether the Component is currently in design mode. (Inherited from Component.)
Public property DestinationQueue Gets the intended destination queue for a message.
Public property DestinationSymmetricKey Gets or sets the symmetric key used to encrypt application-encrypted messages or messages sent to foreign queues.
Public property DigitalSignature Gets or sets the digital signature that Message Queuing uses to authenticate the message.
Public property EncryptionAlgorithm Gets or sets the encryption algorithm used to encrypt the body of a private message.
Protected property Events Gets the list of event handlers that are attached to this Component. (Inherited from Component.)
Public property Extension Gets or sets additional, application-defined information associated with the message.
Public property Formatter Gets or sets the formatter used to serialize an object into or deserialize an object from the message body.
Public property HashAlgorithm Gets or sets the hashing algorithm that Message Queuing uses when authenticating a message or creating a digital signature for a message.
Public property Id Gets the message's identifier.
Public property IsFirstInTransaction Gets a value that indicates whether the message was the first message sent in a transaction.
Public property IsLastInTransaction Gets a value that indicates whether the message was the last message sent in a transaction.
Public property Label Gets or sets an application-defined Unicode string that describes the message.
Public property LookupId Introduced in MSMQ 3.0. Gets the message's lookup identifier.
Public property MessageType Gets the message type: Normal, Acknowledgment, or Report.
Public property Priority Gets or sets the message priority, which determines where in the queue the message is placed.
Public property Recoverable Gets or sets a value that indicates whether the message is guaranteed to be delivered in the event of a computer failure or network problem.
Public property ResponseQueue Gets or sets the queue that receives application-generated response messages.
Public property SecurityContext Gets or sets the security context for a message.
Public property SenderCertificate Gets or sets the security certificate used to authenticate messages.
Public property SenderId Gets the identifier of the sending user.
Public property SenderVersion Gets the version of Message Queuing used to send the message.
Public property SentTime Gets the date and time on the sending computer that the message was sent by the source queue manager.
Public property Site Gets or sets the ISite of the Component. (Inherited from Component.)
Public property SourceMachine Gets the computer from which the message originated.
Public property TimeToBeReceived Gets or sets the maximum amount of time for the message to be received from the destination queue.
Public property TimeToReachQueue Gets or sets the maximum amount of time for the message to reach the queue.
Public property TransactionId Gets the identifier for the transaction of which the message was a part.
Public property TransactionStatusQueue Gets the transaction status queue on the source computer.
Public property UseAuthentication Gets or sets a value that indicates whether the message was (or must be) authenticated before being sent.
Public property UseDeadLetterQueue Gets or sets a value that indicates whether a copy of the message that could not be delivered should be sent to a dead-letter queue.
Public property UseEncryption Gets or sets a value that indicates whether to make the message private.
Public property UseJournalQueue Gets or sets a value that indicates whether a copy of the message should be kept in a machine journal on the originating computer.
Public property UseTracing Gets or sets a value that indicates whether to trace a message as it moves toward its destination queue.
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  Name Description
Public method CreateObjRef Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object. (Inherited from MarshalByRefObject.)
Public method Dispose() Releases all resources used by the Component. (Inherited from Component.)
Protected method Dispose(Boolean) Releases the unmanaged resources used by the Component and optionally releases the managed resources. (Inherited from Component.)
Public method Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected method Finalize Releases unmanaged resources and performs other cleanup operations before the Component is reclaimed by garbage collection. (Inherited from Component.)
Public method GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public method GetLifetimeService Retrieves the current lifetime service object that controls the lifetime policy for this instance. (Inherited from MarshalByRefObject.)
Protected method GetService Returns an object that represents a service provided by the Component or by its Container. (Inherited from Component.)
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Public method InitializeLifetimeService Obtains a lifetime service object to control the lifetime policy for this instance. (Inherited from MarshalByRefObject.)
Protected method MemberwiseClone() Creates a shallow copy of the current Object. (Inherited from Object.)
Protected method MemberwiseClone(Boolean) Creates a shallow copy of the current MarshalByRefObject object. (Inherited from MarshalByRefObject.)
Public method ToString Returns a String containing the name of the Component, if any. This method should not be overridden. (Inherited from Component.)
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  Name Description
Public event Disposed Occurs when the component is disposed by a call to the Dispose method. (Inherited from Component.)
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  Name Description
Public field Static member InfiniteTimeout Specifies that no time-out exists.
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Use the Message class to peek or receive messages from a queue, or to have fine control over message properties when sending a message to a queue.

MessageQueue uses the Message class when it peeks or receives messages from queues, because both the MessageQueue.Peek and MessageQueue.Receive methods create a new instance of the Message class and set the instance's properties. The Message class's read-only properties apply to retrieving messages from a queue, while the read/write properties apply to sending and retrieving messages. When MessageQueue peeks or receives a message from a queue, its MessageReadPropertyFilter property determines which of the message's properties are retrieved.

The MessageQueue class's Send method allows you to specify any object type for a message being sent to that queue. You can use the MessageQueue instance's DefaultPropertiesToSend property to specify settings for generic messages sent to the queue. The types of settings include formatter, label, encryption, and authentication. You can also specify values for the appropriate DefaultPropertiesToSend members when you coordinate your messaging application to respond to acknowledgment and report messages. Using a Message instance to send a message to the queue gives you the flexibility to access and modify many of these properties—either for a single message or on a message-by-message basis. Message properties take precedence over DefaultPropertiesToSend.

Message data is stored in the Body property and to a lesser extent, the AppSpecific and Extension properties. When message data is encrypted, serialized, or deserialized, only the contents of the Body property are affected.

The contents of the Body property are serialized when the message is sent, using the Formatter property you specify. The serialized contents are found in the BodyStream property. You can also set the BodyStream property directly, for example, to send a file as the data content of a message. You can change the Body or Formatter properties at any time before sending the message, and the data will be serialized appropriately when you call Send.

The properties defined by the MessageQueue.DefaultPropertiesToSend property apply only to messages that are not of type Message. If you specify the DefaultPropertiesToSend property for a MessageQueue, the identically named properties in a Message instance sent to that queue cause these default properties to be ignored.

For a list of initial property values for an instance of Message, see the Message constructor.

The following code example demonstrates formatting a message body using 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;
		}
	}
}


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


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;
		}
	}
}


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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