c# - Timer Elapsed 事件如何与高优先级线程竞争？

Question

我有一个要使用的 System.Timers.Timer 对象，但我不希望绑定(bind)到 Timer 的处理干扰普通到高优先级线程。换句话说，我想说我想每 5 秒处理一次 X，只要没有其他东西在运行。

我如何确保我的计时器操作以低优先级方式运行？

Answer 1

System.Timers.Timer 的好处是您可以通过 SynchronizingObject 属性分配一个同步对象，然后利用它来运行 Elapsed 事件优先级可控。

只需将 ElapsedEventReceiver 的实例分配给计时器的 SynchronizingObject 属性即可。

免责声明:我很快就完成了这个，所以您需要添加自己的收尾工作以使其更加健壮。

public class ElapsedEventReceiver : ISynchronizeInvoke
{
    private Thread m_Thread;
    private BlockingCollection<Message> m_Queue = new BlockingCollection<Message>();

    public ElapsedEventReceiver()
    {
        m_Thread = new Thread(Run);
        m_Thread.Priority = ThreadPriority.BelowNormal;
        m_Thread.IsBackground = true;
        m_Thread.Start();
    }

    private void Run()
    {
        while (true)
        {
            Message message = m_Queue.Take();
            message.Return = message.Method.DynamicInvoke(message.Args);
            message.Finished.Set();
        }
    }

    public IAsyncResult BeginInvoke(Delegate method, object[] args)
    {
        Message message = new Message();
        message.Method = method;
        message.Args = args;
        m_Queue.Add(message);
        return message;
    }

    public object EndInvoke(IAsyncResult result)
    {
        Message message = result as Message;
        if (message != null)
        {
            message.Finished.WaitOne();
            return message.Return;
        }
        throw new ArgumentException("result");
    }

    public object Invoke(Delegate method, object[] args)
    {
        Message message = new Message();
        message.Method = method;
        message.Args = args;
        m_Queue.Add(message);
        message.Finished.WaitOne();
        return message.Return;
    }

    public bool InvokeRequired
    {
        get { return Thread.CurrentThread != m_Thread; }
    }

    private class Message : IAsyncResult
    {
        public Delegate Method;
        public object[] Args;
        public object Return;
        public object State;
        public ManualResetEvent Finished = new ManualResetEvent(false);

        public object AsyncState
        {
            get { return State; }
        }

        public WaitHandle AsyncWaitHandle
        {
            get { return Finished; }
        }

        public bool CompletedSynchronously
        {
            get { return false; }
        }

        public bool IsCompleted
        {
            get { return Finished.WaitOne(0); }
        }
    }
}