The Replicator Activity is similar to a foreach programming statement in that it creates and executes multiple instances of a specified child activity. The Collection is prepared and populated using the Initialized handler method. For an example handler see Workflow Basics – Code Snippet.

During execution the replicator fires an event to signal the initialization and completion of each child activity. These handlers are set in the ChildIntialized and ChildCompleted properties respectively. If the UntilCondition property is set the activity will not finish until the condition evaluates to true, so care must be taken that UntilCondition is true when all child activities are completed. If UntilCondition is true before the child activities are all finished, the activity will still finish. If ExecutionType is set to Sequence(the default), the child instances run in sequence. If set to Parallel, all instances get created before the replicator starts. For more information on Replicator Activities see Workflow Basics – Loops and Repeated Activities