EventDrivenActivity Class
Wraps an Activity whose execution is initialized by an event. This class cannot be inherited.
Assembly: System.Workflow.Activities (in System.Workflow.Activities.dll)
System.Workflow.ComponentModel::DependencyObject
System.Workflow.ComponentModel::Activity
System.Workflow.ComponentModel::CompositeActivity
System.Workflow.Activities::SequenceActivity
System.Workflow.Activities::EventDrivenActivity
| Name | Description | |
|---|---|---|
![]() | EventDrivenActivity() | Initializes a new instance of the EventDrivenActivity class. |
![]() | EventDrivenActivity(String^) | Initializes a new instance of the EventDrivenActivity class using the name of the activity. |
| Name | Description | |
|---|---|---|
![]() | Activities | Gets the object representing the collection, ActivityCollection, of all child activities.(Inherited from CompositeActivity.) |
![]() | CanModifyActivities | Gets or sets a value which controls whether the individual activities within Activities can be modified.(Inherited from CompositeActivity.) |
![]() | Description | |
![]() | DesignMode | Gets the value that indicates whether this instance is in design or run-time mode.(Inherited from DependencyObject.) |
![]() | Enabled | Gets or sets a value that indicates whether this instance is enabled for execution and validation.(Inherited from Activity.) |
![]() | EnabledActivities | Gets the read-only collection that represents the subset of Activities that are enabled. (Inherited from CompositeActivity.) |
![]() | EventActivity | Gets the event activity that drives the change. |
![]() | ExecutionResult | Gets the ActivityExecutionResult of the last attempt to run this instance.(Inherited from Activity.) |
![]() | ExecutionStatus | Gets the current ActivityExecutionStatus of this instance.(Inherited from Activity.) |
![]() | IsDynamicActivity | Gets information about whether the activity is executing within the default ActivityExecutionContext of the workflow instance.(Inherited from Activity.) |
![]() | Name | Gets 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.) |
![]() | Parent | Gets the CompositeActivity that contains this Activity.(Inherited from Activity.) |
![]() | QualifiedName | Gets the qualified name of the activity. Qualified activity names are always unique in a workflow instance.(Inherited from Activity.) |
![]() | Site | Gets or sets a reference to the Site component of the DependencyObject.(Inherited from DependencyObject.) |
![]() | UserData | Gets an IDictionary that associates custom data with this class instance.(Inherited from DependencyObject.) |
| Name | Description | |
|---|---|---|
![]() | Canceling | Occurs when the activity execution is canceled. (Inherited from Activity.) |
![]() | Closed | |
![]() | Compensating | |
![]() | Executing | |
![]() | Faulting | Occurs when an exception is raised during the running of the instance.(Inherited from Activity.) |
![]() | StatusChanged | Occurs when the ActivityExecutionStatus of a running Activity changes.(Inherited from Activity.) |
| Name | Description | |
|---|---|---|
![]() ![]() | IComponent::Disposed | Represents the method that handles the Disposed event of a component.(Inherited from DependencyObject.) |
![]() ![]() | IActivityEventListener<ActivityExecutionStatusChangedEventArgs^>::OnEvent(Object^, ActivityExecutionStatusChangedEventArgs^) | Defines the processing procedure when the subscribed-to event occurs.(Inherited from SequenceActivity.) |
Note |
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This material discusses types and namespaces that are obsolete. For more information, see Deprecated Types in Windows Workflow Foundation 4.5. |
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:
The EventDrivenActivity may contain one, and only one, activity of type IEventActivity.
The HandleExternalEventActivity must be the first child activity. An HandleExternalEventActivity cannot be in the event handler for a child activity and cannot be a child to the EventDrivenActivity if the HandleExternalEventActivity is not the first child.
As long as the first activity is the HandleExternalEventActivity, the event handler can contain any activities. If an activity other than HandleExternalEventActivity is contained in EventDrivenActivity, that activity cannot have an event handler.
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.
Available since 3.0
Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
System.Workflow.Activities Namespace
Using the EventDriven Activity








