Parallel 类并行任务（仅仅当执行耗时操作时，才有必要使用）

using System;

using System.Collections.Generic;

using System.Diagnostics;

using System.Linq;

using System.Text;

using System.Threading;

using System.Threading.Tasks;

namespace ConsoleApplication1

{

    class Program

    {

        static void Main(string[] args)

        {

            Stopwatch sw = new Stopwatch();

            sw.Start();

            ////非并行任务，总耗时间：3000

            //Thread.Sleep(1000);

            //Thread.Sleep(2000);

            ////并行任务，总耗时间：2000

            //Parallel.Invoke(() =>

            //{

            //    Thread.Sleep(1000);

            //}, () =>

            //{

            //    Thread.Sleep(2000);

            //});

            List<int> list = new List<int>();

            var len = ;

            object _olock = new object();

            var count = ; //用户计算大于5000数的个数

            for (int i = ; i < ; i++)

            {

                list.Add(i);

            }

            len = list.Count;

            Parallel.For(, len, (i) =>

            {

                lock (_olock)

                {

                    //耗时操作

                    Thread.Sleep();

                    if (i > )

                    {

                        count++;

                    }

                }

            });

            sw.Stop();

            Console.WriteLine(sw.ElapsedMilliseconds);

            Console.Read();

        }

    }

}