使用demo，（.net framework 4.0 自行添加async wait 扩展库）
class Program
{
static void Main(string[] args)
{
Console.WriteLine("主线程"+Thread.CurrentThread.ManagedThreadId);
var asyncTaskQueue = new AsyncTaskQueue
{
AutoCancelPreviousTask = true, // 自动取消之前的任务
UseSingleThread = true // 使用单线程执行任务
}; // 快速启动20个任务
for (var i = ; i < ; i++)
{
Test(asyncTaskQueue, i);
}
Console.WriteLine("运行结束");
Console.ReadKey();
} public static async void Test(AsyncTaskQueue taskQueue, int num)
{
var result = await taskQueue.Run(() =>
{
// 长时间耗时任务
Thread.Sleep();
Console.WriteLine("输入的是" + num);
return num * ;
});
Console.WriteLine("当前线程" + Thread.CurrentThread.ManagedThreadId + "输出的的" + result);
}
}
这里是实现代码
#region summary // ------------------------------------------------------------------------------------------------
// <copyright file="AsyncTaskQueue.cs" >
// 作者：mokeyish
// </copyright>
// ------------------------------------------------------------------------------------------------ #endregion using System;
using System.Collections.Concurrent;
using System.Diagnostics;
using System.Security.Permissions;
using System.Runtime.CompilerServices;
using System.Threading;
using System.Threading.Tasks; namespace Test
{
/// <summary>
/// 异步任务队列
/// </summary>
public class AsyncTaskQueue : IDisposable
{
private bool _isDisposed;
private readonly ConcurrentQueue<AwaitableTask> _queue = new ConcurrentQueue<AwaitableTask>();
private Thread _thread;
private AutoResetEvent _autoResetEvent; /// <summary>
/// 异步任务队列
/// </summary>
public AsyncTaskQueue()
{
_autoResetEvent = new AutoResetEvent(false);
_thread = new Thread(InternalRuning) {IsBackground = true};
_thread.Start();
} private bool TryGetNextTask(out AwaitableTask task)
{
task = null;
while (_queue.Count > )
{
if (_queue.TryDequeue(out task) && (!AutoCancelPreviousTask || _queue.Count == )) return true;
task.Cancel();
}
return false;
} private AwaitableTask PenddingTask(AwaitableTask task)
{
lock (_queue)
{
Debug.Assert(task != null);
_queue.Enqueue(task);
_autoResetEvent.Set();
}
return task;
} private void InternalRuning()
{
while (!_isDisposed)
{
if (_queue.Count == )
{
_autoResetEvent.WaitOne();
}
while (TryGetNextTask(out var task))
{
if (task.IsCancel) continue; if (UseSingleThread)
{
task.RunSynchronously();
}
else
{
task.Start();
}
}
}
} /// <summary>
/// 是否使用单线程完成任务.
/// </summary>
public bool UseSingleThread { get; set; } = true; /// <summary>
/// 自动取消以前的任务。
/// </summary>
public bool AutoCancelPreviousTask { get; set; } = false; /// <summary>
/// 执行任务
/// </summary>
/// <param name="action"></param>
/// <returns></returns>
public AwaitableTask Run(Action action)
=> PenddingTask(new AwaitableTask(new Task(action, new CancellationToken(false)))); /// <summary>
/// 执行任务
/// </summary>
/// <typeparam name="TResult"></typeparam>
/// <param name="function"></param>
/// <returns></returns>
public AwaitableTask<TResult> Run<TResult>(Func<TResult> function)
=> (AwaitableTask<TResult>) PenddingTask(new AwaitableTask<TResult>(new Task<TResult>(function))); /// <inheritdoc />
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
} /// <summary>
/// 析构任务队列
/// </summary>
~AsyncTaskQueue() => Dispose(false); private void Dispose(bool disposing)
{
if (_isDisposed) return;
if (disposing)
{
_autoResetEvent.Dispose();
}
_thread = null;
_autoResetEvent = null;
_isDisposed = true;
} /// <summary>
/// 可等待的任务
/// </summary>
public class AwaitableTask
{
private readonly Task _task; /// <summary>
/// 初始化可等待的任务。
/// </summary>
/// <param name="task"></param>
public AwaitableTask(Task task) => _task = task; /// <summary>
/// 任务的Id
/// </summary>
public int TaskId => _task.Id; /// <summary>
/// 任务是否取消
/// </summary>
public bool IsCancel { get; private set; } /// <summary>
/// 开始任务
/// </summary>
public void Start() => _task.Start(); /// <summary>
/// 同步执行开始任务
/// </summary>
public void RunSynchronously() => _task.RunSynchronously(); /// <summary>
/// 取消任务
/// </summary>
public void Cancel() => IsCancel = true; /// <summary>
/// 获取任务等待器
/// </summary>
/// <returns></returns>
public TaskAwaiter GetAwaiter() => new TaskAwaiter(this); /// <summary>Provides an object that waits for the completion of an asynchronous task. </summary>
[HostProtection(SecurityAction.LinkDemand, ExternalThreading = true, Synchronization = true)]
public struct TaskAwaiter : INotifyCompletion
{
private readonly AwaitableTask _task; /// <summary>
/// 任务等待器
/// </summary>
/// <param name="awaitableTask"></param>
public TaskAwaiter(AwaitableTask awaitableTask) => _task = awaitableTask; /// <summary>
/// 任务是否完成.
/// </summary>
public bool IsCompleted => _task._task.IsCompleted; /// <inheritdoc />
public void OnCompleted(Action continuation)
{
var This = this;
_task._task.ContinueWith(t =>
{
if (!This._task.IsCancel) continuation?.Invoke();
});
}
/// <summary>
/// 获取任务结果
/// </summary>
public void GetResult() => _task._task.Wait();
}
} /// <summary>
/// 可等待的任务
/// </summary>
/// <typeparam name="TResult"></typeparam>
public class AwaitableTask<TResult> : AwaitableTask
{
/// <summary>
/// 初始化可等待的任务
/// </summary>
/// <param name="task">需要执行的任务</param>
public AwaitableTask(Task<TResult> task) : base(task) => _task = task; private readonly Task<TResult> _task; /// <summary>
/// 获取任务等待器
/// </summary>
/// <returns></returns>
public new TaskAwaiter GetAwaiter() => new TaskAwaiter(this); /// <summary>
/// 任务等待器
/// </summary>
[HostProtection(SecurityAction.LinkDemand, ExternalThreading = true, Synchronization = true)]
public new struct TaskAwaiter : INotifyCompletion
{
private readonly AwaitableTask<TResult> _task; /// <summary>
/// 初始化任务等待器
/// </summary>
/// <param name="awaitableTask"></param>
public TaskAwaiter(AwaitableTask<TResult> awaitableTask) => _task = awaitableTask; /// <summary>
/// 任务是否已完成。
/// </summary>
public bool IsCompleted => _task._task.IsCompleted; /// <inheritdoc />
public void OnCompleted(Action continuation)
{
var This = this;
_task._task.ContinueWith(t =>
{
if (!This._task.IsCancel) continuation?.Invoke();
});
} /// <summary>
/// 获取任务结果。
/// </summary>
/// <returns></returns>
public TResult GetResult() => _task._task.Result;
}
}
}
}