Simple Game in C# with only native libraries

Here's a simple game using WinForms and a Timer, using Graphics to draw (encapsulates GDI+).

It adds a timer that 'ticks' every 10 milliseconds. Each tick it performs game logic, then draws to an off screen bitmap. This is as opposed to using a continual loop as in the example in the link.

The form handles key events separately (as opposed to doing something like GetKeyState)

When the form is resized, and when it first loads it'll create the backbuffer bitmap of the right size.

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Create a new form and replace all code with below. Control the ball using arrow keys. There's no notion of dying.

using System;
using System.Drawing;
using System.Windows.Forms;

namespace WindowsFormsGame
{
    public partial class Form1 : Form
    {
        Bitmap Backbuffer;

        const int BallAxisSpeed = 2;

        Point BallPos = new Point(30, 30);
        Point BallSpeed = new Point(BallAxisSpeed, BallAxisSpeed);
        const int BallSize = 50;

        public Form1()
        {
            InitializeComponent();

            this.SetStyle(
            ControlStyles.UserPaint |
            ControlStyles.AllPaintingInWmPaint |
            ControlStyles.DoubleBuffer, true);

            Timer GameTimer = new Timer();
            GameTimer.Interval = 10;
            GameTimer.Tick += new EventHandler(GameTimer_Tick);
            GameTimer.Start();

            this.ResizeEnd += new EventHandler(Form1_CreateBackBuffer);
            this.Load += new EventHandler(Form1_CreateBackBuffer);
            this.Paint += new PaintEventHandler(Form1_Paint);

            this.KeyDown += new KeyEventHandler(Form1_KeyDown);
        }

        void Form1_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Left)
                BallSpeed.X = -BallAxisSpeed;
            else if (e.KeyCode == Keys.Right)
                BallSpeed.X = BallAxisSpeed;
            else if (e.KeyCode == Keys.Up)
                BallSpeed.Y = -BallAxisSpeed; // Y axis is downwards so -ve is up.
            else if (e.KeyCode == Keys.Down)
                BallSpeed.Y = BallAxisSpeed;
        }

        void Form1_Paint(object sender, PaintEventArgs e)
        {
            if (Backbuffer != null)
            {
                e.Graphics.DrawImageUnscaled(Backbuffer, Point.Empty);
            }
        }

        void Form1_CreateBackBuffer(object sender, EventArgs e)
        {
            if (Backbuffer != null)
                Backbuffer.Dispose();

            Backbuffer = new Bitmap(ClientSize.Width, ClientSize.Height);
        }

        void Draw()
        {
            if (Backbuffer != null)
            {
                using (var g = Graphics.FromImage(Backbuffer))
                {
                    g.Clear(Color.White);
                    g.FillEllipse(Brushes.Black, BallPos.X - BallSize / 2, BallPos.Y - BallSize / 2, BallSize, BallSize);
                }

                Invalidate();
            }
        }

        void GameTimer_Tick(object sender, EventArgs e)
        {
            BallPos.X += BallSpeed.X;
            BallPos.Y += BallSpeed.Y;


            Draw();

            // TODO: Add the notion of dying (disable the timer and show a message box or something)
        }
    }
}