多线程结束时间判断出现的问题？ 求高人解答

Question

  private   void ScanWithMultThreads(string subIP, int start, int end)
        {          int ipCount = end - start + 1;
          DateTime starttime = new DateTime();
          starttime = DateTime.Now;
          Thread[] scanThreads=new Thread[ipCount];
         for(int i=0;i<ipCount;i++)
         {
           Scan scan=new Scan
         {  
                      ip=string.Format("{0},{1}",subIP,start+1),
           form=this};
           scanThreads[i]=new Thread(scan.CheckComputer);
           scanThreads[i].IsBackground=true;
           scanThreads[i].Start();
           ThreadPool.QueueUserWorkItem(new WaitCallback(testMethod), scanThreads[i]);
                   }
         WaitHandle.WaitAll(scanThreads);
         listBoxStatus.Items.Add("扫描用时为：" + (DateTime.Now - starttime).TotalMilliseconds);       
       }  
       public void testMethod(object objEvent)
       {
           //TODO: Add your code here
           ManualResetEvent e = (ManualResetEvent)objEvent;
           e.Set();
       }
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这是部分代码 程序运行后 出现两个错误 如下：
错误 2 参数 1: 无法从“System.Threading.Thread[]”转换为“System.Threading.WaitHandle[]” C:\Users\liu\documents\visual studio 2010\Projects\ScanComputer\ScanComputer\MainForm.cs 75 29 ScanComputer
错误 1 与“System.Threading.WaitHandle.WaitAll(System.Threading.WaitHandle[])”最匹配的重载方法具有一些无效参数 C:\Users\liu\documents\visual studio 2010\Projects\ScanComputer\ScanComputer\MainForm.cs 75 10 ScanComputer
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求高人指点 到底哪个地方错误 尽量详细些 嘿嘿 多谢

Answer 1

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这个scanThreads参数吗 类型是Thread[]类型的 帮看看错？

Answer 2

WaitAll的参数类型不对，看看帮助吧

Answer 3

WaitHandle.WaitAll(scanThreads);  参数错误，要的是waithandle类型，传入的是Thread【】。可以把resetevent作为参数传入