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MessageQueue.Receive Method (TimeSpan, MessageQueueTransactionType)

Receives the first message available in the queue referenced by the MessageQueue. This call is synchronous, and waits until either a message is available in the queue, or the time-out expires.

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

public Message Receive (
	TimeSpan timeout,
	MessageQueueTransactionType transactionType
)
public Message Receive (
	TimeSpan timeout, 
	MessageQueueTransactionType transactionType
)
public function Receive (
	timeout : TimeSpan, 
	transactionType : MessageQueueTransactionType
) : Message

Parameters

timeout

A TimeSpan that indicates the time to wait until a new message is available for inspection.

transactionType

One of the MessageQueueTransactionType values, describing the type of transaction context to associate with the message.

Return Value

A Message that references the first message available in the queue.

Exception typeCondition

ArgumentException

The value specified for the timeout parameter is not valid, possibly timeout is less than TimeSpan.Zero or greater than MessageQueue.InfiniteTimeout.

InvalidEnumArgumentException

The transactionType parameter is not one of the MessageQueueTransactionType members.

MessageQueueException

A message did not arrive in the queue before the time-out expired.

-or-

An error occurred when accessing a Message Queuing method.

Use this overload to receive a message from a queue using a transaction context defined by the transactionType parameter, and return in a specified period of time if there are no messages in the queue.

Specify Automatic for the transactionType parameter if there is already an external transaction context attached to the thread that you want to use to receive the message. Specify Single if you want to receive the message as a single internal transaction. You can specify None if you want to receive a message from a transactional queue outside of a transaction context.

The Receive method allows for the synchronous reading of a message, thereby removing it from the queue. Subsequent calls to Receive will return the messages that follow in the queue.

If this method is called to receive a message from a transactional queue, the message that is received would be returned to the queue if the transaction is aborted. The message is not permanently removed from the queue until the transaction is committed.

To read the first message in a queue without removing it from the queue, use the Peek method. The Peek method always returns the first message in the queue, so subsequent calls to the method return the same message unless a higher priority message arrives in the queue. There is no transaction context associated with a message returned by a call to Peek. Because Peek does not remove any messages in the queue, there would be nothing to roll back by a call to Abort.

Use a call to Receive when it is acceptable for the current thread to be blocked while it waits for a message to arrive in the queue. The thread will be blocked for the given period of time, or indefinitely if you specified the value InfiniteTimeout for the timeout parameter. If the application processing should continue without waiting for a message, consider using the asynchronous method, BeginReceive.

The following table shows whether this method is available in various Workgroup modes.

Workgroup mode

Available

Local computer

Yes

Local computer and direct format name

Yes

Remote computer

No

Remote computer and direct format name

Yes

The following code example demonstrates the use of this method.


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

// Create a new message.
Message msg = new Message("Example Message Body");

// Send the message.
queue.Send(msg, MessageQueueTransactionType.Single);

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

// Receive the message from the queue. Because the Id of the message
// is not specified, it might not be the message just sent.
msg = queue.Receive(TimeSpan.FromSeconds(10.0),
    MessageQueueTransactionType.Single);


// Connect to a transactional queue on the local computer.
MessageQueue queue = new MessageQueue(".\\exampleTransQueue");
// Create a new message.
Message msg = new Message("Example Message Body");
// Send the message.
queue.Send(msg, MessageQueueTransactionType.Single);
// Set the formatter to indicate the message body contains a String.
queue.set_Formatter(new XmlMessageFormatter(new Type[] 
    { String.class.ToType() }));
// Receive the message from the queue. Because the Id of the message
// is not specified, it might not be the message just sent.
msg = queue.Receive(TimeSpan.FromSeconds(10.0),
    MessageQueueTransactionType.Single);

  • Full trust for the immediate caller. This member cannot be used by partially trusted code. For more information, see .

Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

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

.NET Framework

Supported in: 2.0, 1.1, 1.0

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