异步等待（ManualResetEvent

ManualResetEvent实现异步等待，超过时间 不做处理，继续往下执行代码

（ManualResetEvent 涉及一个线程在其他线程进行之前必须完成的任务）

 ManualResetEvent[] mre = new ManualResetEvent[];

             mre[] = new ManualResetEvent(false);
             shoppingbll spb = new shoppingbll(mre[], dict);
             Thread thd1 = new Thread(new ThreadStart(spb.GetGPrice));
             thd1.Start();

             mre[] = new ManualResetEvent(false);
             farebll pfb = new farebll(mre[], dict);
             Thread thd2 = new Thread(new ThreadStart(pfb.GetfarePrice));
             thd2.Start();

             //停顿12s 超过12s后，执行后面代码，不再等待
             WaitHandle.WaitAll(mre, , false);

GetGPrice 方法（GetfarePrice类似） ，调用ManualResetEvent 的set()方法  返回信号；

public void GetGPrice()
        {
            try
            {
                 //todo
            }
            catch (Exception e)
            {

            }
            finally
            {
                if (_mre != null)
                {
                    _mre.Set();//返回完成信号
                }
            }
        }

Task（任务）类似用法：

             Task t1 = new Task(func);//无返回值
             Task<int> t2 = new Task<int>(()=>canshufun());//有返回值(带参数
             Task<int> t3 = new Task<int>(() => intfun());//有返回值（无参数           

             Task[] tt = new Task[] { t1, t2 ,t3};
             Task.WaitAll(tt,  * );//10秒后 不再等待，往后执行
             int result2 = t2.Result;//获取返回结果
             int result3 = t3.Result;//获取返回结果        

 public void func()
         { }

         public int intfun()
         {
             return ;
         }
         public int canshufun(int i)
         {
             return i;
         }

Task 通过CancellationTokenSource参数 取消超时线程任务

 /// <summary>
         /// 返回政策
         /// </summary>
         /// <param name="dept">出发</param>
         /// <param name="arr">到达</param>
         /// <param name="depttime">出发日期</param>
         /// <param name="arrtime">返程日期</param>
         /// <param name="from">政策源</param>
         /// <param name="carriers">航司</param>
         /// <param name="cabinlevels">舱位等级（First, Business, Economy）</param>
         /// <param name="ftype">1,直飞;2,所有</param>
         /// <param name="number">返回数量</param>
         /// <param name="second">超时时间</param>
         /// <param name="iresponsetime">国际接口返回时间</param>
         /// <param name="nresponsetime">国内接口返回时间</param>
         /// <returns></returns>
         public model.PolicyCacheModel Get(string dept, string arr, string depttime, string arrtime, string from, string carriers, string cabinlevels, string ftype, int number, int second, ref int iresponsetime, ref int nresponsetime)
         {
             List<string> policies = from.Split('|').ToList();
             List<string> gj = new List<string>();
             List<string> gn = new List<string>();
             foreach (string s in policies)
             {
                 if(s.Contains("12,")) gj.Add(s);
                 else if (s.Contains("18,")) gj.Add(s);
                 else if (s.Contains("20,")) gn.Add(s);
                 else if (s.Contains("50,")) gj.Add(s);
                 else gn.Add(s);
             }

             if (gj.Count ==  && gn.Count == ) return null;

             Task<model.CompareModel> gjtask = null;
             Task<model.CompareModel> gntask = null;
             CancellationTokenSource gjct = null;
             CancellationTokenSource gnct = null;
             List<Task<model.CompareModel>> tasks = new List<Task<model.CompareModel>>();

             if (gj.Count > )
             {
                 gjct = new CancellationTokenSource();
                 gjtask = new Task<model.CompareModel>(() => GetInternational(dept, arr, depttime, arrtime, from, carriers, cabinlevels, ftype, number, second), gjct.Token);
                 tasks.Add(gjtask);
             }
             if (gn.Count > )
             {
                 gnct = new CancellationTokenSource();
                 gntask = new Task<model.CompareModel>(() => GetNational(dept, arr, depttime, arrtime, from, carriers, cabinlevels, ftype, number, second), gnct.Token);
                 tasks.Add(gntask);
             }

             if (gjtask != null) gjtask.Start();
             if (gntask != null) gntask.Start();
             Task.WaitAll(tasks.ToArray(), second * );

             model.CompareModel m1 = null;
             model.CompareModel m2 = null;
             if (gjtask != null)
             {
                 if (gjtask.Status == TaskStatus.RanToCompletion) m1 = gjtask.Result;
                 else gjct.Cancel();
             }
             if (gntask != null)
             {
                 if (gntask.Status == TaskStatus.RanToCompletion) m2 = gntask.Result;
                 else gnct.Cancel();
             }

             try
             {
                 model.CompareModel d = InMatch(m1, m2);
                 model.PolicyCacheModel m3 = MatchRebate(d);
                 return m3;
             }
             catch (Exception ex)
             {
                 return null;
             }
         }

参考：

http://www.cnblogs.com/li-peng/p/3291306.html

http://www.cnblogs.com/springyangwc/archive/2011/10/12/2208991.html