private void buttonStart_Click(object sender, EventArgs e)
        {
            timerRed.Start();
        } 


       private void timerRed_Tick(object sender, EventArgs e)
       {
           timerGreen.Stop();
           redLight.FillColor = Color.Red;            
           greenLight.FillColor = Color.Black;
            timerRed.Stop();
            timerYellow.Start();
        }
        private void timerYellow_Tick(object sender, EventArgs e)
        {
            timerRed.Stop();
            yellowLight.FillColor = Color.Yellow;
            redLight.FillColor = Color.Black;
            timerYellow.Stop();
            timerGreen.Start();
        }
        private void timerGreen_Tick(object sender, EventArgs e)
        {
            timerGreen.Stop();
            greenLight.FillColor = Color.Green;
            yellowLight.FillColor = Color.Black;
            timerGreen.Stop();
            timerRed.Start();
        }

private Timer lightTimer;
private TrafficLight trafficLight;
public TrafficLightController()
   {
       lightTimer = new Timer();
       lightTimer.Interval = 1000;
       lightTimer.Elapsed += lightTimer_Elapsed;
       trafficLight = new TrafficLight();
    }

namespace TrafficLightSim
{
    public class TrafficLight
    {
        public ITrafficLight State
        { get; set; }

        public Image Display
        {
            get
            {
                return State.Display;
            }
        }

        public TrafficLight()
        {
            State = new TrafficLightOff();
        }

        public void Change()
        {
            State.Change(this);
        }
    }
}