PeekCompletedEventHandler Delegate

 
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Represents the method that will handle the PeekCompleted event of a MessageQueue.

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

Public Delegate Sub PeekCompletedEventHandler (
	sender As Object,
	e As PeekCompletedEventArgs
)

Parameters

sender
Type: System.Object

The source of the event, the MessageQueue.

e
Type: System.Messaging.PeekCompletedEventArgs

A PeekCompletedEventArgs that contains the event data.

When you create a PeekCompletedEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event-handler delegates, see NIB: Events and Delegates.

The following example illustrates how to create an event delegate (PeekCompletedEventHandler) for the event handler (MyPeekCompleted) and associate it with the MessageQueue.PeekCompleted event. The event handler peeks a message and writes its label to the screen.

Imports System
Imports System.Messaging





' Provides a container class for the example.
Public Class MyNewQueue



        ' Provides an entry point into the application.
        '		 
        ' This example performs asynchronous peek operation
        ' processing.


        Public Shared Sub Main()
            ' Create an instance of MessageQueue. Set its formatter.
            Dim myQueue As New MessageQueue(".\myQueue")
            myQueue.Formatter = New XmlMessageFormatter(New Type() _
                {GetType([String])})

            ' Add an event handler for the PeekCompleted event.
            AddHandler myQueue.PeekCompleted, AddressOf _
                MyPeekCompleted

            ' Begin the asynchronous peek operation.
            myQueue.BeginPeek()

            ' Do other work on the current thread.
            Return
        End Sub 'Main


        '**************************************************
        ' Provides an event handler for the PeekCompleted
        ' event.
        '**************************************************

        Private Shared Sub MyPeekCompleted(ByVal [source] As _
            [Object], ByVal asyncResult As PeekCompletedEventArgs)

            ' Connect to the queue.
            Dim mq As MessageQueue = CType([source], MessageQueue)

            ' End the asynchronous peek operation.
            Dim m As Message = mq.EndPeek(asyncResult.AsyncResult)

            ' Display message information on the screen.
            Console.WriteLine(("Message: " + CStr(m.Body)))

            ' Restart the asynchronous peek operation.
            mq.BeginPeek()

            Return

        End Sub 'MyPeekCompleted

End Class 'MyNewQueue

.NET Framework
Available since 1.1
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