c# 实现计时器功能

System.Windows.Forms.Timer _timer = new System.Windows.Forms.Timer();

_timer.Interval = 1000;

_timer.Tick +=_timer_Tick;

private void _timer_Tick(object sender, EventArgs e)
  {
    //执行的业务
  }

_timer.Start();

_timer.Stop();

System.Timers.Timer _timerWaterTank = new System.Timers.Timer(1000);//实例化Timer类，设置间隔时间为1000毫秒； 

_timerWaterTank.Elapsed += new System.Timers.ElapsedEventHandler(_timerWaterTank_Tick);//到达时间的时候执行事件；

_timerWaterTank.AutoReset = true;//设置是执行一次（false）还是一直执行(true)；

private void _timerWaterTank_Tick(object sender, EventArgs e)
      {
        System.Timers.Timer timer = sender as System.Timers.Timer;
        //要计时的时间秒数
        this.LowLevelSecondsWaterTank--;
        if (this.LowLevelSecondsWaterTank <= 0)
        {
          //倒计时结束后执行的业务
          Global.PublicVar.Instance.IsGoOnMonitorWaterPool = true;
          timer.Enabled = false;
          this.LowLevelSecondsWaterTank = Global.LOW_LEVEL_MONITOR_SECONDS;
          
        }
      }

timer.Enabled = true;

timer.Enabled = false;