This method enables client code to remove items from the collection by using a foreach loop (For Each in Visual Basic), or System.Threading.Tasks.Parallel.ForEach``1(Partitioner<``0>, Action<``0>) or a PLINQ query. The enumerator will continue to provide items (if any exist) until BlockingCollection`1.IsCompleted returns true, and if BlockingCollection`1.IsCompleted is false the loop blocks until an item becomes available or until the System.Threading.CancellationToken is cancelled.