Introducing .NET 4.0 Parallel Programming

//--------------------------------------------------------------------------
// 
//  Copyright (c) Microsoft Corporation.  All rights reserved. 
// 
//  File: ThreadPerTaskScheduler.cs
//
//--------------------------------------------------------------------------

using System.Collections.Generic;
using System.Linq;

namespace System.Threading.Tasks.Schedulers
{
    /// <summary>Provides a task scheduler that dedicates a thread per task.</summary>
    public class ThreadPerTaskScheduler : TaskScheduler
    {
        /// <summary>Gets the tasks currently scheduled to this scheduler.</summary>
        /// <remarks>This will always return an empty enumerable, as tasks are launched as soon as they're queued.</remarks>
        protected override IEnumerable<Task> GetScheduledTasks() { return Enumerable.Empty<Task>(); }

        /// <summary>Starts a new thread to process the provided task.</summary>
        /// <param name="task">The task to be executed.</param>
        protected override void QueueTask(Task task)
        {
            new Thread(() => TryExecuteTask(task)) { IsBackground = true }.Start();
        }

        /// <summary>Runs the provided task on the current thread.</summary>
        /// <param name="task">The task to be executed.</param>
        /// <param name="taskWasPreviouslyQueued">Ignored.</param>
        /// <returns>Whether the task could be executed on the current thread.</returns>
        protected override bool TryExecuteTaskInline(Task task, bool taskWasPreviouslyQueued)
        {
            return TryExecuteTask(task);
        }
    }
}