public Timer Regist(Action<Timer> callback, float interval, int times, TimerStateType state = TimerStateType.Normal)
 {
     Timer timer = new Timer(callback, interval, times, state);
     _timers.Add(timer);
     return timer;
 }
 //移除一个计时器
 public void Remove(Timer timer)
 {
     if (_timers.Contains(timer)) _timers.Remove(timer);
 }
 //注册一个计时器
 public Timer Regist(Timer timer)
 {
     _timers.Add(timer);
     return timer;
 }