namespace ConsoleTest
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("********同步調用開始**********");
            int result = Add(1,2);
            Console.WriteLine("同步調用完畢，執行結果為:" + result);

            Console.WriteLine("********異步調用開始**********");
            SynAdd(1, 2, (r) => {
                Console.WriteLine("異步調用完畢，執行結果為:" + r);
            });
            Console.WriteLine("-------完畢！----------");
            Console.ReadLine();
        }

        /// <summary>
        /// 同步方法
        /// </summary>
        /// <param name="a"></param>
        /// <param name="b"></param>
        /// <returns></returns>
        static int Add(int a, int b)
        {
            Thread.Sleep(5000);
            return a + b;
        }

        /// <summary>
        /// 異步調用
        /// </summary>
        /// <param name="a"></param>
        /// <param name="b"></param>
        /// <param name="callback">委托對象</param>
        static void SynAdd(int a, int b, Action<int> callback)
        {
            Func<int> func = () =>
            {
                Thread.Sleep(5000);
                return a+b;
            };//聲明異步方法實現方式
            func.BeginInvoke((ar) =>
            {
                var result = func.EndInvoke(ar);//調用完畢執行的結果
                callback.Invoke(result);//委托執行，回傳結果值
            }, null);
        }
    }
}