C# 多线程实践

以下工具会把一个总任务拆分成多个子任务，交给多个线程同时执行。使用时只需要传入线程数，总任务列表和执行方法即可。

MultiThreadProcessor

using System;
using System.Collections.Generic;
using System.Threading;

namespace ConsoleTest
{
    public class MultiThreadProcessor<T>
    {
        public MultiThreadProcessor(int _threadCount, Action<List<T>> _action)
        {
            threadCount = _threadCount;
            waitingThreadCount = _threadCount;
            action = _action;
        }

        private int threadCount;
        private int waitingThreadCount;
        private AutoResetEvent autoEvent;
        private Action<List<T>> action;
        public void MultiTaskExecute(List<T> taskList)
        {
            autoEvent = new AutoResetEvent(false);

            int totalCount = taskList.Count;
            int lastProcessCount = totalCount % (threadCount - 1);
            int perThreadProcessCount = (totalCount - lastProcessCount) / (threadCount - 1);

            int takeIndex = 0;
            int threadTakeCount = perThreadProcessCount;
            for (int threadIndex = 1; threadIndex <= threadCount; threadIndex++)
            {
                List<T> executeList = new List<T>();

                if (threadIndex == threadCount)
                {
                    threadTakeCount = lastProcessCount;
                }
                int endIndex = takeIndex + threadTakeCount;
                for (; takeIndex < endIndex; takeIndex++)
                {
                    executeList.Add(taskList[takeIndex]);
                }

                ThreadPool.QueueUserWorkItem(new WaitCallback(DoTask), executeList);
            }

            autoEvent.WaitOne();
        }

        private void DoTask(object obj)
        { 
            List<T> list = obj as List<T>;
            if (list != null && list.Count > 0)
            {
                action.Invoke(list);
            }
            if (Interlocked.Decrement(ref waitingThreadCount) == 0)
            {
                autoEvent.Set();
            }
        }
    }
}

使用示例

using System;
using System.Collections.Generic;
using System.Threading;

namespace ConsoleTest
{
    class Program
    {
        List<int> totalTasks = new List<int>();
        for (int i = 0; i< 37; i++)
        {
            totalTasks.Add(i);
        }
        MultiThreadProcessor<int> threadTool = new MultiThreadProcessor<int>(10, ExecuteTask);
        threadTool.MultiTaskExecute(totalTasks);
        Console.WriteLine("Process End!");
        Console.ReadLine();
    }

    private static void ExecuteTask(List<int> list)
    {
        Random rd = new Random();
        Thread.Sleep(rd.Next(1, 1000));
        Console.WriteLine($"{string.Join(',', list)}, Count: {list.Count}");
    }
}