FillEllipse: Red Traffic Light

   
 

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Windows.Forms;

class Form1 : Form {
    private int lightColor = 1;

    public Form1() {
        InitializeComponent();
    }

    private void Form1_Paint(object sender, PaintEventArgs e) {
        Graphics g = e.Graphics;

        g.FillRectangle(Brushes.White, this.ClientRectangle);
        Rectangle r = new Rectangle(10, 10, 60, 180);
        g.FillRectangle(Brushes.LightGray, r);
        Rectangle r1 = new Rectangle(10, 10, 60, 60);
        Rectangle r2 = new Rectangle(10, 70, 60, 60);
        Rectangle r3 = new Rectangle(10, 130, 60, 60);
        switch (lightColor) {
            case 1:
                g.FillEllipse(Brushes.Red, r1);
                g.FillEllipse(Brushes.Black, r2);
                g.FillEllipse(Brushes.Black, r3);
                break;
            case 2:
                g.FillEllipse(Brushes.Black, r1);
                g.FillEllipse(Brushes.Yellow, r2);
                g.FillEllipse(Brushes.Black, r3);
                break;
            case 3:
                g.FillEllipse(Brushes.Black, r1);
                g.FillEllipse(Brushes.Black, r2);
                g.FillEllipse(Brushes.Green, r3);
                break;
        }
    }

    private void Form1_Click(object sender, EventArgs e) {
        lightColor++;
        if (lightColor == 4)
            lightColor = 1;
        this.Invalidate();
    }
    private void InitializeComponent() {
        this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
        this.ClientSize = new System.Drawing.Size(292, 271);
        this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
        this.Click += new System.EventHandler(this.Form1_Click);
    }

    [STAThread]
    static void Main() {
        Application.EnableVisualStyles();
        Application.Run(new Form1());
    }

}