WorkflowQueue.UnregisterForQueueItemAvailable Method

Reference

Definition

Namespace:: System.Workflow.Runtime

Assembly:: System.Workflow.Runtime.dll

Important

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Unregisters a subscriber to the QueueItemAvailable event.

public:
 void UnregisterForQueueItemAvailable(System::Workflow::ComponentModel::IActivityEventListener<System::Workflow::ComponentModel::QueueEventArgs ^> ^ eventListener);

public void UnregisterForQueueItemAvailable (System.Workflow.ComponentModel.IActivityEventListener<System.Workflow.ComponentModel.QueueEventArgs> eventListener);

member this.UnregisterForQueueItemAvailable : System.Workflow.ComponentModel.IActivityEventListener<System.Workflow.ComponentModel.QueueEventArgs> -> unit

Public Sub UnregisterForQueueItemAvailable (eventListener As IActivityEventListener(Of QueueEventArgs))

Parameters

eventListener: IActivityEventListener<QueueEventArgs>

A subscriber for QueueEventArgs that implements the IActivityEventListener<T> interface.

Exceptions

ArgumentNullException

eventListener is a null reference (Nothing in Visual Basic).

Examples

The following code example demonstrates how you can create a WorkflowQueue by calling the WorkflowQueuingService.GetWorkflowQueue method. It also uses the UnregisterForQueueItemAvailable to unregister the specified listener.

This code example is part of the File Watcher Activity SDK Sample from the FileSystemEvent.cs file. For more information, see File System Watcher Activity.

private void DoUnsubscribe(ActivityExecutionContext context, IActivityEventListener<QueueEventArgs> listener)
{
    if (!this.subscriptionId.Equals(Guid.Empty))
    {
        FileWatcherService fileService = context.GetService<FileWatcherService>();
        fileService.UnregisterListener(this.subscriptionId);
        this.subscriptionId = Guid.Empty;
    }

    WorkflowQueuingService qService = context.GetService<WorkflowQueuingService>();
    WorkflowQueue queue = qService.GetWorkflowQueue(this.QueueName);

    queue.UnregisterForQueueItemAvailable(listener);
}

Private Sub DoUnsubscribe(ByVal context As ActivityExecutionContext, ByVal listener As IActivityEventListener(Of QueueEventArgs))
    If Not Me.subscriptionId.Equals(Guid.Empty) Then
        Dim fileService As FileWatcherService = context.GetService(Of FileWatcherService)()
        fileService.UnregisterListener(Me.subscriptionId)
        Me.subscriptionId = Guid.Empty
    End If

    Dim qService As WorkflowQueuingService = context.GetService(Of WorkflowQueuingService)()
    Dim queue As WorkflowQueue = qService.GetWorkflowQueue(Me.QueueName)
    queue.UnregisterForQueueItemAvailable(listener)
End Sub

Applies to

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