class Program    {        static void Main(string[] args)        {            Func<int> func = new Func<int>(GetInt);            var iar = func.BeginInvoke(new AsyncCallback(Show), null);            while (!iar.IsCompleted)            {                Thread.Sleep(1000);                Console.WriteLine("收到了您的提示！");            }            Console.WriteLine("处理结果为{0}！",func.EndInvoke(iar));            Console.ReadKey();        }        private static void Show(IAsyncResult iar)        {            while (iar.IsCompleted)            {                Console.WriteLine("执行完毕！");                break;            }        }        private static int GetInt()        {            for (var i = 0; i < 10; i++)            {                Console.WriteLine("请稍等，我正在执行，需要点时间");                Thread.Sleep(1000);            }            return 1;        }    }