Parallel小记

   　　　　　　List<Temp> tList = new List<Temp>();
             for (int i = ; i < ; i++)
             {
                 tList.Add(new Temp()
                 {
                     id = i,
                     name = string.Concat("test", i),
                     age = i *
                 });
             }
             object obj = new object();
             List<TempChild> resultList = new List<TempChild>();
             Stopwatch sc = new Stopwatch();
             Stopwatch sc1 = new Stopwatch();
             Stopwatch sc2 = new Stopwatch();
             sc.Start();
             Parallel.ForEach(tList, item =>
             {
                 List<TempChild> tempChildList = LoadChildList();
                 if (null != tempChildList && tempChildList.Count > )
                 {
                     lock (obj)//一定要加锁，不然会出异常【目标数组长度不够，请检查destIndex和长度以及数组下限】
                     {
                         resultList.AddRange(tempChildList);
                     }
                 }
             });
             sc.Stop();
             long second = sc.ElapsedMilliseconds;
             List<TempChild> resultList1 = new List<TempChild>();
             sc1.Start();
             foreach (var item in tList)
             {
                 List<TempChild> tempChildList = LoadChildList();
                 if (null != tempChildList && tempChildList.Count > )
                 {
                     resultList1.AddRange(tempChildList);
                 }
             }
             sc1.Stop();
             long second2 = sc1.ElapsedMilliseconds;

             sc2.Start();
             List<TempChild> resultList2 = tList
                 .AsParallel()
                 .SelectMany(
                 (item) =>
                 {
                     return LoadChildList();
                 }).ToList();
             sc2.Stop();
             long second3 = sc2.ElapsedMilliseconds;

   private static List<TempChild> LoadChildList()
        {
            List<TempChild> tList = new List<TempChild>();
            for (int i = 1; i < 100; i++)
            {
                tList.Add(new TempChild()
                {
                    id = i,
                    name = string.Concat("test", i),
                    age = i * 2,
                    addr = i.ToString()
                });
            }
            return tList;
        }

　　分别对不同数据量级的并行任务执行对比，三种方式结果如下：

　　

　　

　　

　　

　　

　　百万数量级，电脑崩了，没有测试结果~@@！！

　　由此，一般的list没必要并行执行，foreach足以。