Producer-consumer class from C#5.0 in a Nutshell, Chap 23 p.954

Producer-consumer class

using System;
using System.Collections.Concurrent;
using System.Threading;
using System.Threading.Tasks;

namespace PcQueue
{
    /// <summary>
    /// Producer-consumer class from C#5.0 in a Nutshell, Chap 23 p.954
    /// </summary>
    public class ProducerConsumerQueue : IDisposable
    {
        BlockingCollection<Task> _taskQ = new BlockingCollection<Task>();

        public ProducerConsumerQueue(int workerCount)
        {
            // Create and start a separate Task for each consumer:
            for (int i = 0; i < workerCount; i++)
                Task.Factory.StartNew(Consume);
        }

        public Task EnqueueTask(Action action, CancellationToken cancelToken = default(CancellationToken))
        {
            var task = new Task(action, cancelToken);
            _taskQ.Add(task);
            return task;
        }

        public Task<TResult> Enqueue<TResult>(Func<TResult> func, CancellationToken cancelToken = default(CancellationToken))
        {
            var task = new Task<TResult>(func, cancelToken);
            _taskQ.Add(task);
            return task;
        }

        public int Length
        {
            get { return _taskQ.Count; }
        }

        void Consume()
        {
            foreach (var task in _taskQ.GetConsumingEnumerable())
                try {
                    if (!task.IsCanceled) task.RunSynchronously();
                } catch (InvalidOperationException) { } // Race condition
        }

        public void Dispose() { _taskQ.CompleteAdding(); }
    }
}