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EventDrivenActivity Class

Wraps an Activity whose execution is initialized by an event. This class cannot be inherited.

Namespace:  System.Workflow.Activities
Assembly:  System.Workflow.Activities (in System.Workflow.Activities.dll)

[<ToolboxBitmapAttribute(typeof(EventDrivenActivity), "Resources.EventDriven.png")>]
type EventDrivenActivity =  
        inherit SequenceActivity

The EventDrivenActivity type exposes the following members.

Public methodEventDrivenActivity()Initializes a new instance of the EventDrivenActivity class.
Public methodEventDrivenActivity(String)Initializes a new instance of the EventDrivenActivity class using the name of the activity.

Public propertyActivitiesGets the object representing the collection, ActivityCollection, of all child activities. (Inherited from CompositeActivity.)
Protected propertyCanModifyActivitiesGets or sets a value which controls whether the individual activities within Activities can be modified. (Inherited from CompositeActivity.)
Public propertyDescriptionGets or sets the user-defined description of the Activity. (Inherited from Activity.)
Protected propertyDesignModeGets the value that indicates whether this instance is in design or run-time mode. (Inherited from DependencyObject.)
Public propertyEnabledGets or sets a value that indicates whether this instance is enabled for execution and validation. (Inherited from Activity.)
Public propertyEnabledActivitiesGets the read-only collection that represents the subset of Activities that are enabled. (Inherited from CompositeActivity.)
Public propertyEventActivityGets the event activity that drives the change.
Public propertyExecutionResultGets the ActivityExecutionResult of the last attempt to run this instance. (Inherited from Activity.)
Public propertyExecutionStatusGets the current ActivityExecutionStatus of this instance. (Inherited from Activity.)
Public propertyIsDynamicActivityGets information about whether the activity is executing within the default ActivityExecutionContext of the workflow instance. (Inherited from Activity.)
Public propertyNameGets or sets the name of this instance. This name must conform to the variable naming convention of the programming language that is being used in the Workflow project. (Inherited from Activity.)
Public propertyParentGets the CompositeActivity that contains this Activity. (Inherited from Activity.)
Protected propertyParentDependencyObjectGets the parent DependencyObject in the DependencyObject graph. (Inherited from DependencyObject.)
Public propertyQualifiedNameGets the qualified name of the activity. Qualified activity names are always unique in a workflow instance. (Inherited from Activity.)
Public propertySiteGets or sets a reference to the Site component of the DependencyObject. (Inherited from DependencyObject.)
Public propertyUserDataGets an IDictionary that associates custom data with this class instance. (Inherited from DependencyObject.)
Protected propertyWorkflowInstanceIdGets the Guid associated with the instance. (Inherited from Activity.)

Public methodAddHandlerAdds a handler for an event of a DependencyObject. (Inherited from DependencyObject.)
Protected methodApplyWorkflowChangesApplies the WorkflowChanges manifest in the parameter to this instance. (Inherited from CompositeActivity.)
Protected methodCancelCancels the execution of the activity. (Inherited from SequenceActivity.)
Public methodCloneCreates a deep copy of the Activity. (Inherited from Activity.)
Public methodDispose()Releases all the resources used by the DependencyObject. (Inherited from DependencyObject.)
Protected methodDispose(Boolean)Calls Dispose on this instance, and optionally calls Dispose on all child activities of this instance. (Inherited from CompositeActivity.)
Public methodEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodExecuteExecutes the activity. (Inherited from SequenceActivity.)
Protected methodFinalizeProvided as an override to Object.Finalize to clean up any unmanaged resources deterministically. (Inherited from DependencyObject.)
Public methodGetActivityByName(String)Returns the instance of the Activity whose name is requested from the set of all activities running under the root activity of this instance, which is within the workflow. (Inherited from Activity.)
Public methodGetActivityByName(String, Boolean)Returns the instance of the Activity whose name is requested from the set of all activities under the root the Activity of this instance if the second parameter is false and under the current Activity if the second parameter is true. (Inherited from Activity.)
Public methodGetBindingProvides access to the ActivityBind associated with the specific DependencyProperty. (Inherited from DependencyObject.)
Protected methodGetBoundValueRetrieves the Object that is the subject of an ActivityBind. (Inherited from DependencyObject.)
Protected methodGetDynamicActivitiesReturns an array that contains all of the currently executing instances of the specified activity. (Inherited from CompositeActivity.)
Public methodGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Protected methodGetInvocationList(T)Gets an array that contains the delegates for the specified DependencyProperty. (Inherited from DependencyObject.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodGetValueProvides access to the value of the designated DependencyProperty. (Inherited from DependencyObject.)
Public methodGetValueBaseProvides access to the bound object of a DependencyProperty and bypasses the GetValue override. (Inherited from DependencyObject.)
Protected methodHandleFaultCalled when an exception is raised within the context of the execution of this instance. (Inherited from SequenceActivity.)
Protected methodInitializeInitializes all appropriate child activities of this instance and the specified IServiceProvider. (Inherited from CompositeActivity.)
Protected methodInitializePropertiesPerforms initialization on dependency properties when overridden in a derived class. (Inherited from DependencyObject.)
Protected methodInvoke(T)(EventHandler(T), T)Subscribes an EventHandler and invokes that delegate. (Inherited from Activity.)
Protected methodInvoke(T)(IActivityEventListener(T), T)Subscribes an IActivityEventListener(T) and invokes that delegate. (Inherited from Activity.)
Public methodIsBindingSetIndicates whether the value of a DependencyProperty is set as a binding. See SetBinding. (Inherited from DependencyObject.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodMetaEqualsDetermines whether the metaproperties of this DependencyObject equals the metaproperties of the parameterized DependencyObject. (Inherited from DependencyObject.)
Protected methodOnActivityChangeAddCalls when an activity is added. (Inherited from CompositeActivity.)
Protected methodOnActivityChangeRemoveCalled when an activity is removed. (Inherited from SequenceActivity.)
Protected methodOnActivityExecutionContextLoadCalled by the workflow runtime engine every time the ActivityExecutionContext for this activity is loaded. (Inherited from CompositeActivity.)
Protected methodOnActivityExecutionContextUnloadCalled by the workflow runtime engine every time the ActivityExecutionContext for this activity is unloaded. (Inherited from CompositeActivity.)
Protected methodOnClosedCalled by the workflow runtime as part of the activity's transition to the closed state. (Inherited from Activity.)
Protected methodOnListChangedPerforms additional processing when the Activities property changes. (Inherited from CompositeActivity.)
Protected methodOnListChangingEvent that occurs before a change being made to the underlying Activities. (Inherited from CompositeActivity.)
Protected methodOnSequenceCompleteWhen overridden in a derived class, determines the action taken by the SequenceActivity when the activity has completed execution. (Inherited from SequenceActivity.)
Protected methodOnWorkflowChangesCompletedCalled after changes have been made to the collection Activities of this instance. (Inherited from SequenceActivity.)
Protected methodRaiseEventRaises an Event associated with the specified dependency property. (Inherited from Activity.)
Protected methodRaiseGenericEvent(T)Raises the event associated with the referenced DependencyProperty. (Inherited from Activity.)
Public methodRegisterForStatusChangeRegisters the specified DependencyProperty for the status change event. (Inherited from Activity.)
Public methodRemoveHandlerRemoves an EventHandler from an associated DependencyProperty. (Inherited from DependencyObject.)
Public methodRemovePropertyRemoves a DependencyProperty from the DependencyObject. (Inherited from DependencyObject.)
Public methodSave(Stream)Writes the Activity to a Stream for persistence. (Inherited from Activity.)
Public methodSave(Stream, IFormatter)Writes the Activity to a Stream for persistence using the custom IFormatter provided for serialization. (Inherited from Activity.)
Public methodSetBindingSets the ActivityBind for the specified DependencyProperty. (Inherited from DependencyObject.)
Protected methodSetBoundValueSets the value of the target ActivityBind. (Inherited from DependencyObject.)
Protected methodSetReadOnlyPropertyValueSets the value of a DependencyProperty, which is read-only. (Inherited from DependencyObject.)
Public methodSetValueSets the value of the DependencyProperty to the object. (Inherited from DependencyObject.)
Public methodSetValueBaseSets the value of the DependencyProperty to the specified Object, bypassing the SetValue. (Inherited from DependencyObject.)
Public methodToStringProvides a string that represents this instance. (Inherited from Activity.)
Protected methodTrackData(Object)Informs the run-time tracking infrastructure of pending tracking information. (Inherited from Activity.)
Protected methodTrackData(String, Object)Informs the run-time tracking infrastructure of pending tracking information. (Inherited from Activity.)
Protected methodUninitializeCalled by the workflow runtime engine when an activity transitions into the Closed state from the Initialized state. (Inherited from CompositeActivity.)
Public methodUnregisterForStatusChangeUn-registers the specified DependencyProperty for the status change event. (Inherited from Activity.)

Public eventCancelingOccurs when the activity execution is canceled. (Inherited from Activity.)
Public eventClosedOccurs when an Activity has completed execution. (Inherited from Activity.)
Public eventCompensatingOccurs when running a compensation method on the Activity. (Inherited from Activity.)
Public eventExecutingOccurs when the Activity is run. (Inherited from Activity.)
Public eventFaultingOccurs when an exception is raised during the running of the instance. (Inherited from Activity.)
Public eventStatusChangedOccurs when the ActivityExecutionStatus of a running Activity changes. (Inherited from Activity.)

Explicit interface implemetationPrivate methodIActivityEventListener(ActivityExecutionStatusChangedEventArgs).OnEventDefines the processing procedure when the subscribed-to event occurs. (Inherited from SequenceActivity.)
Explicit interface implemetationPrivate eventIComponent.DisposedRepresents the method that handles the Disposed event of a component. (Inherited from DependencyObject.)

It is a CompositeActivity that is used to handle an event; typically it can be raised from the host or by the runtime in response to a delay timer expiring. EventDrivenActivity is inherited from SequenceActivity; therefore, it is a sequence that has the additional restriction that the first activity should be an IEventActivity.

The EventDrivenActivity is a CompositeActivity, which means the EventDrivenActivity can contain other activities. The EventDrivenActivity is similar to the SequenceActivity activity, with some additional characteristics.

An EventDrivenActivity must have a parent that is either a ListenActivity, StateActivity, or StateMachineWorkflowActivity.

The first child of an EventDrivenActivity activity must be an activity that inherits from IEventActivity. All subsequent children can be activities of any type. The IEventActivity blocks and waits for the pending occurrence of some events, such as starting a timer or the arrival of a message. When the event occurs, the IEventActivity finishes running and then all subsequent activities are executed.

When the StateMachineWorkflowActivity contains an EventDrivenActivity, the EventDrivenActivity has some restrictions:

For example, an activity that supports event handling can be used inside the EventDrivenActivity but the activity cannot have event handlers attached to itself.

Another example is that the EventDrivenActivity can contain a ConditionedActivityGroup, but the ConditionedActivityGroup itself cannot contain any HandleExternalEventActivity classes.

The following code example shows how to use the EventDrivenActivity to perform state machine transitions. This code example is part of the SimpleStateMachineWorkflow SDK sample from the StateMachineWorkflow.cs file. For more information, seeSimple State Machine.

No code example is currently available or this language may not be supported.

.NET Framework

Supported in: 4, 3.5, 3.0

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.