异步调用函数

 static class Program
    {
        /// <summary>
        /// 应用程序的主入口点。
        /// </summary>
        [STAThread]
        static void Main()
        {
            addMethod = new AddDelegate(Add);
            addMethod.BeginInvoke(0, 1, new AsyncCallback(CompleteMethod), "主线程");
        }
	//声明委托
        public delegate int AddDelegate(int a, int b);
        public static AddDelegate addMethod;
	//函数
        public static int Add(int a, int b)
        {
            Thread.Sleep(5000);
            return a + b;
        }

        private static void CompleteMethod(IAsyncResult async)
        {
            if (async.IsCompleted)
            {
                int d = addMethod.EndInvoke(async);
            }
        }
    }