c#异步

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication4
{
    class Program
      {
          static void Main(string[] args)
          {
             Console.WriteLine("同步调用开始=>");
             int a = SyncAdd(1, 2);
             Console.WriteLine("同步调用结束：" + a);
 
             Console.WriteLine("--------------------------");
 
             Console.WriteLine("异步调用开始=>");
             AyscAdd(3, 4, (result) =>
             {
                 Console.WriteLine("异步调用结果：" + result);
             });
             Console.WriteLine("异步调用结束");
 
             Console.ReadLine();
         }
 
         /// <summary>
         /// 异步调用
         /// </summary>
         /// <param name="a"></param>
         /// <param name="b"></param>
         /// <param name="callBackAction"></param>
         /// <returns></returns>
         static void AyscAdd(int a, int b, Action<int> callBackAction)
         {
             Func<int> func = () =>
             {
                 return new MyMath().Add(a, b);
             };
             func.BeginInvoke((ar) =>
             {
                 var result = func.EndInvoke(ar);
                 callBackAction.Invoke(result);
             },
             null);
 
         }
 
         /// <summary>
         /// 同步调用
         /// </summary>
         /// <param name="a"></param>
         /// <param name="b"></param>
         /// <returns></returns>
         static int SyncAdd(int a, int b)
         {
             return new MyMath().Add(a, b);
         }
     }
 
     public class MyMath
     {
 
         public int Add(int a, int b)
         {
             System.Threading.Thread.Sleep(5000);
             return a + b;
         }
 
     }
}