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I see cancellationhandleractivity on any compositeactivity type. I try everything, but i didn't see activity in cancellationhandleractivity box run.
So, When do they run?
and Can i force activity to run cancellationhandleractivity or change state to cancel? How?
I see cancel method in all activity but it is used by workflowruntime. It seems developers can't touch or reach it. Is it true?
ps. dotNetFramework 3.5
Thank for your kind.

Hi,
"The
CancellationHandlerActivity activity contains cleanup logic for a composite activity that is canceled before all the composite activity's child activities are finished executing. A
CancellationHandlerActivity activity cannot exist on its own; it is always associated with another activity.
For example, a
ListenActivity activity or a
ConditionedActivityGroup activity can have multiple child branch activities executing at once. A specific condition, such as an arriving message, can cause the entire activity to close immediately, before all the child activities are finished executing.
The parent activity then cancels the execution of all uncompleted child activities, and their corresponding
CancellationHandlerActivity activity is called to perform the cleanup logic defined there."
http://msdn.microsoft.com/en-us/library/aa349442.aspx
->and Can i force activity to run cancellationhandleractivity or change state to cancel? How?
->I see cancel method in all activity but it is used by workflowruntime. It seems developers can't touch or reach it. Is it true?
We can only cancel an activity from parent, you can refer to:
ActivityExecutionContext.CancelActivity Method
http://msdn.microsoft.com/en-us/library/system.workflow.componentmodel.activityexecutioncontext.cancelactivity.aspxLeo Tang [MSFT]
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