C#-Four模式在异步执行中

Question

我听说异步执行有四种模式.

"异步委托执行有四种模式:轮询,等待完成,完成通知和"消防和忘记".

当我有以下代码时:

class AsynchronousDemo
{
    public static int numberofFeets = 0;
    public delegate long StatisticalData();

    static void Main()
    {
        StatisticalData data = ClimbSmallHill;
        IAsyncResult ar = data.BeginInvoke(null, null);
        while (!ar.IsCompleted)
        {
            Console.WriteLine("...Climbing yet to be completed.....");
            Thread.Sleep(200);

        }
        Console.WriteLine("..Climbing is completed...");
        Console.WriteLine("... Time Taken for  climbing ....{0}", 
        data.EndInvoke(ar).ToString()+"..Seconds");
        Console.ReadKey(true);

    }


    static long ClimbSmallHill()
    {
        var sw = Stopwatch.StartNew();
        while (numberofFeets <= 10000)
        {
            numberofFeets = numberofFeets + 100;
            Thread.Sleep(10);
        }
        sw.Stop();
        return sw.ElapsedMilliseconds;
    }
}

1)上述代码实现的模式是什么？

2)你能解释一下代码,我该如何实现其余的代码？

Answer 1

你有什么轮询模式.在这种模式中,你不断问"我们还在吗？" 该while循环是做阻塞.所述Thread.Sleep防止吃起来的CPU周期的过程.

等待完成是"我会打电话给你"的方法.

IAsyncResult ar = data.BeginInvoke(null, null);
//wait until processing is done with WaitOne
//you can do other actions before this if needed
ar.AsyncWaitHandle.WaitOne(); 
Console.WriteLine("..Climbing is completed...");

因此,一旦WaitOne被召唤,你就会阻止攀爬完成.您可以在阻止之前执行其他任务.

完成通知后,您说"你打电话给我,我不会打电话给你."

IAsyncResult ar = data.BeginInvoke(Callback, null);

//Automatically gets called after climbing is complete because we specified this
//in the call to BeginInvoke
public static void Callback(IAsyncResult result) {
    Console.WriteLine("..Climbing is completed...");
}

这里没有阻止因为Callback会被通知.

而且会发生火灾和遗忘

data.BeginInvoke(null, null);
//don't care about result

这里也没有阻挡,因为攀爬完成时你并不在意.顾名思义,你会忘记它.你说的是"不要打电话给我,我不会打电话给你,但是,不要打电话给我."