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WorkflowEventArgs Class

  • Reference

Definition

Namespace:
System.Workflow.Runtime
Assembly:
System.Workflow.Runtime.dll

Caution

The System.Workflow.* types are deprecated. Instead, please use the new types from System.Activities.*

Provides data for workflow events.

public ref class WorkflowEventArgs : EventArgs
public class WorkflowEventArgs : EventArgs
[System.Obsolete("The System.Workflow.* types are deprecated.  Instead, please use the new types from System.Activities.*")]
public class WorkflowEventArgs : EventArgs
type WorkflowEventArgs = class
    inherit EventArgs
[<System.Obsolete("The System.Workflow.* types are deprecated.  Instead, please use the new types from System.Activities.*")>]
type WorkflowEventArgs = class
    inherit EventArgs
Public Class WorkflowEventArgs
Inherits EventArgs
Inheritance
Object
EventArgs
WorkflowEventArgs
Derived
Attributes
ObsoleteAttribute

Examples

The following code example demonstrates how to obtain a WorkflowInstance object using the WorkflowInstance property when an event handler method is called. When the WorkflowIdled event occurs, the OnWorkflowIdled method defined in this example is called. It determines which workflow is idled using the WorkflowInstance property and then gets a collection of queued items for the workflow instance by calling the GetWorkflowQueueData method. The code iterates over the collection to determine which activity is waiting for the event that idled the workflow. It then sends an exception to the workflow queue using the EnqueueItem method along with the name of the event queue item.

This code example is part of the Canceling a Workflow SDK Sample from the Program.cs file. For more information, see Canceling a Workflow.

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

Remarks

Note

This material discusses types and namespaces that are obsolete. For more information, see Deprecated Types in Windows Workflow Foundation 4.5.

Workflow events are associated with a workflow instance. A WorkflowEventArgs contains the WorkflowInstance associated with the workflow event. A WorkflowEventArgs or an object that derives from the WorkflowEventArgs class provides the data for all of the workflow events in the WorkflowRuntime class. WorkflowEventArgs is the base class for WorkflowCompletedEventArgs, WorkflowSuspendedEventArgs, and WorkflowTerminatedEventArgs.

Properties

WorkflowInstance

Gets the workflow instance associated with the workflow event.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also