Question

Please see below pseudo code

//Single or multiple Producers produce using below method
    void Produce(object itemToQueue)
    {
        concurrentQueue.enqueue(itemToQueue);
        consumerSignal.set;
    }

    //somewhere else we have started a consumer like this
    //we have only one consumer
    void StartConsumer()
    {
        while (!concurrentQueue.IsEmpty())
        {
            if (concurrentQueue.TrydeQueue(out item))
            {
                //long running processing of item
            }
        }
        consumerSignal.WaitOne();
    }

How do I port this pattern I have used since time immemorial to use taskfactory created tasks and the new signalling features of net 4. In other words if someone were to write this pattern using net 4 how would it look like ? Pseudo code is fine. Iam already using .net 4 concurrentQueue as you can see. How do I use a task and possibly use some newer signalling mechanism if possible. thanks

Solution to my problem below thanks to Jon/Dan. Sweet.
No manual signalling or while(true) or while(itemstoProcess) type loops like the old days

//Single or multiple Producers produce using below method
 void Produce(object itemToQueue)
 {
     blockingCollection.add(item);
 }

 //somewhere else we have started a consumer like this
 //this supports multiple consumers !
 task(StartConsuming()).Start; 

 void StartConsuming()
 {
     foreach (object item in blockingCollection.GetConsumingEnumerable())
     {
                //long running processing of item
     }
 }

cancellations are handled using cancel tokens

Answer 1

You would use BlockingCollection<T>. There’s an example in the documentation.

That class is specifically designed to make this trivial.