C# 多线程任务分配辅助类

1)首先实现一个多线程的辅助类,代码如下:

public class ThreadMulti
  {
      public delegate void DelegateComplete();
      public delegate void DelegateWork(int taskindex,int threadindex);
 
      public DelegateComplete CompleteEvent;
      public DelegateWork WorkMethod;
 
 
      private ManualResetEvent[] _resets;
      private int _taskCount = 0;
      private int _threadCount = 5;
 
      public ThreadMulti(int taskcount)
      {
          _taskCount = taskcount;
      }
 
      public ThreadMulti(int taskcount, int threadCount)
      {
          _taskCount = taskcount;
          _threadCount = threadCount;
      }
 
      public void Start()
      {
          if (_taskCount < _threadCount)
          {
              //任务数小于线程数的
              _resets = new ManualResetEvent[_taskCount];
              for (int j = 0; j < _taskCount; j++)
              {
                  _resets[j] = new ManualResetEvent(false);
                  ThreadPool.QueueUserWorkItem(new WaitCallback(Work), new object[] { j, j });
              }
          }
          else
          {
              _resets = new ManualResetEvent[_threadCount];
              //任务数大于线程数 先把线程数的任务启动
              for (int i = 0; i < _threadCount; i++)
              {
                  _resets[i] = new ManualResetEvent(false);
                  ThreadPool.QueueUserWorkItem(new WaitCallback(Work), new object[] { i, i });
              }
              //完成一个任务后在利用完成的那个线程执行下一个任务
              int receivereset = 0;
              receivereset = ManualResetEvent.WaitAny(_resets);
              for (int l = _threadCount; l < _taskCount; l++)
              {
                  _resets[receivereset].Reset();
                  ThreadPool.QueueUserWorkItem(new WaitCallback(Work), new object[] { l, receivereset });
                  receivereset = ManualResetEvent.WaitAny(_resets);
              }
          }
 
          ManualResetEvent.WaitAll(_resets);
          if (CompleteEvent != null)
          {
              CompleteEvent();
          }
      }
 
      public void Work(object arg)
      {
          int taskindex = int.Parse(((object[])arg)[0].ToString());
          int resetindex = int.Parse(((object[])arg)[1].ToString());
          if (WorkMethod != null)
          {
              WorkMethod(taskindex + 1, resetindex+1);
          }
          _resets[resetindex].Set();
      }
  }

  ThreadMulti类能够根据根据传入的任务数和线程数,实现多线程的重复利用并执行指定的WorkMethod.
  并且在任务完成后能触发CompleteEvent事件.
  类中关键的是ManualResetEvent类的应用,能够在一个任务完成时通知程序哪个线程执行完毕,然后就安排另一个任务开始执行.

 

 

 

2)辅助类的应用

           //实例化多线程辅助类并启动
     ThreadMulti thread = new ThreadMulti(workcount);
 
     thread.WorkMethod = new ThreadMulti.DelegateWork(DoWork);//执行任务的函数
     thread.CompleteEvent = new ThreadMulti.DelegateComplete(WorkComplete);//所有任务执行完毕的事件
     thread.Start();

只需要指定任务数和执行任务的函数和完成任务后的事件即可.调用Start方法后,DoWork会在线程中调用并传递任务的index和执行线程的index.

public void DoWork(int index,int threadindex)
      {
      }