Generic .Net Producer/Consumer

Question

I'm toying with the idea of implementing a generic Producer/Consumer pair + processing queue in C# for fun. The idea is you can just create objects that implement appropriate IProducer and IConsumer interfaces (default implementations supplied), which will consist mainly of delegates, pass them to a QueueProcessor class instance, tell it how many consumers you want, and go.

But I say to myself, "Self, surely this has been done before."

So does anyone know of a good, generic implementation of the producer/consumer pattern in C# (VB.Net is okay, too)? The basic requirements I'm looking for:

• Use generics for the produced and consumed types (input, queued task, and output types, or any combination thereof)
• Allow you specify how many consumers will work the queue
• Allow you to link up or chain multiple queues into a pipeline (tricky with multiple Consumers, I know)
• Allow you to implement your own Producers and Consumers
• Allow you to turn any IEnumerable into a producer (okay if I have to implement that myself, as long it's possible)
• Delegate based (you can use lambda syntax for the basic consumer or producer work to process a single item)

Or if there is none, what pitfalls have prevented it and do you have any thoughts on how to implement it?

Answer 1

Microsoft CCR contains much of what you need.

Here are some code samples and usage notes.

Answer 2

Marc Gravell wrote a nice example blocking queue in this answer.