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TimerEventSubscription Class

Represents a subscription to a timer event.

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

public class TimerEventSubscription

TimerEventSubscription objects are added to the timer queue associated with a workflow instance in order to send a message to a specific WorkflowQueue at a specified time. When the time specified by ExpiresAt is reached, the workflow runtime engine sends a message containing the SubscriptionId to the WorkflowQueue specified by QueueName. The timer queue associated with a workflow instance is contained in the TimerCollectionProperty. You can examine TimerCollectionProperty and the WorkflowQueueInfo objects returned by WorkflowInstance.GetWorkflowQueueData to determine which activities are waiting on a specific TimerEventSubscription. The DelayActivity and the SqlWorkflowPersistenceService both use timer event subscriptions to provide part of their functionality.


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

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

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

.NET Framework

Supported in: 3.5, 3.0