WorkflowEventArgs.WorkflowInstance Proprietà

Definizione

Spazio dei nomi:

System.Workflow.Runtime

Assembly:

System.Workflow.Runtime.dll

Ottiene un'istanza del flusso di lavoro associata all'evento del flusso di lavoro.

public:
 property System::Workflow::Runtime::WorkflowInstance ^ WorkflowInstance { System::Workflow::Runtime::WorkflowInstance ^ get(); };

public System.Workflow.Runtime.WorkflowInstance WorkflowInstance { get; }

member this.WorkflowInstance : System.Workflow.Runtime.WorkflowInstance

Public ReadOnly Property WorkflowInstance As WorkflowInstance

Valore della proprietà

WorkflowInstance

WorkflowInstance associato all'evento del flusso di lavoro.

Esempio

Nell'esempio di codice seguente viene illustrato come ottenere un oggetto WorkflowInstance utilizzando la proprietà WorkflowInstance quando viene chiamato un metodo del gestore eventi. Quando si verifica l'evento WorkflowIdled viene chiamato il metodo OnWorkflowIdled definito in questo esempio. Determina quale flusso di lavoro venga reso inattivo mediante la proprietà WorkflowInstance e quindi ottiene una raccolta di elementi in coda per l'istanza del flusso di lavoro chiamando il metodo GetWorkflowQueueData. Il codice scorre la raccolta per determinare quale attività è in attesa dell'evento che ha sospeso il flusso di lavoro. Invia quindi un'eccezione alla coda del flusso di lavoro mediante il metodo EnqueueItem insieme al nome dell'elemento in coda dell'evento.

Questo esempio di codice fa parte dell'esempio SDK Canceling a Workflow nel file Program.cs. Per altre informazioni, vedere Annullamento di un flusso di lavoro.

static void OnWorkflowIdled(object sender, WorkflowEventArgs e)
{
    WorkflowInstance workflow = e.WorkflowInstance;

    Console.WriteLine("\n...waiting for 3 seconds... \n");
    Thread.Sleep(3000);

    // what activity is blocking the workflow
    ReadOnlyCollection<WorkflowQueueInfo> wqi = workflow.GetWorkflowQueueData();
    foreach (WorkflowQueueInfo q in wqi)
    {
        EventQueueName eq = q.QueueName as EventQueueName;
        if (eq != null)
        {
            // get activity that is waiting for event
            ReadOnlyCollection<string> blockedActivity = q.SubscribedActivityNames;
            Console.WriteLine("Host: Workflow is blocked on " + blockedActivity[0]);

            // this event is never going to arrive eg. employee left the company
            // lets send an exception to this queue
            // it will either be handled by exception handler that was modeled in workflow
            // or the runtime will unwind running compensation handlers and exit the workflow
            Console.WriteLine("Host: This event is not going to arrive");
            Console.WriteLine("Host: Cancel workflow with unhandled exception");
            workflow.EnqueueItem(q.QueueName, new Exception("ExitWorkflowException"), null, null);
        }
    }
}

Shared Sub OnWorkflowIdled(ByVal sender As Object, ByVal e As WorkflowEventArgs)
    Dim workflow As WorkflowInstance = e.WorkflowInstance

    Console.WriteLine(vbCrLf + "...waiting for 3 seconds... " + vbCrLf)
    Thread.Sleep(3000)

    ' what activity is blocking the workflow
    Dim wqi As ReadOnlyCollection(Of WorkflowQueueInfo) = workflow.GetWorkflowQueueData()
    For Each q As WorkflowQueueInfo In wqi

        Dim eq As EventQueueName = TryCast(q.QueueName, EventQueueName)

        If eq IsNot Nothing Then
            ' get activity that is waiting for event
            Dim blockedActivity As ReadOnlyCollection(Of String) = q.SubscribedActivityNames
            Console.WriteLine("Host: Workflow is blocked on " + blockedActivity(0))

            ' this event is never going to arrive eg. employee left the company
            ' lets send an exception to this queue
            ' it will either be handled by exception handler that was modeled in workflow
            ' or the runtime will unwind running compensation handlers and exit the workflow
            Console.WriteLine("Host: This event is not going to arrive")
            Console.WriteLine("Host: Cancel workflow with unhandled exception")
            workflow.EnqueueItem(q.QueueName, New Exception("ExitWorkflowException"), Nothing, Nothing)
        End If
    Next
End Sub

Vedi anche

• Annullamento di un flusso di lavoro