//结束计时
 public void Stop()
 {
     if (UnixHelper.OS == "windows")
     {
         QueryPerformanceCounter(out stopTime);
     }
     else
     {
         UnixHelper.QueryPerformanceCounter(out stopTime);
     }
 }
 //开始计时
 public void Start()
 {
     //让等待线程工作
     System.Threading.Thread.Sleep(0);
     if (UnixHelper.OS == "windows")
     {
         QueryPerformanceCounter(out startTime);
     }
     else
     {
         UnixHelper.QueryPerformanceCounter(out startTime);
     }
 }
 //构造函数
 public HiPerfTimer()
 {
     startTime = 0;
     stopTime  = 0;
     if (UnixHelper.OS == "windows")
     {
         if (QueryPerformanceFrequency(out Frequence) == false)
         {
             //不支持高性能计时器
             throw new System.ComponentModel.Win32Exception();
         }
     }
     else
     {
         UnixHelper.QueryPerformanceFrequency(out Frequence);
     }
 }