Snake Game [C#]

Hello again. I wrote a snake game in C#, let me tell you a little bit about it:

The game features two classes of sprites: Vertebra, representing a single snake link; and Pizza, which is, of course, the pizza.
Each of these classes inherits from the PictureBox class, and uses a Timer for a nice animation when these objects appear.

Game pause is achieved simply by start and stop of the game Timer.

There is a top 10 high scores, which is stored in an xml file.
This file is created automatically on the first time it is requested by the game.
The handling of the high scores is done with LINQ to XML, which is awesome!

Here is the code for the Main form: using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Xml.Linq; using System.Text; using System.Windows.Forms; namespace Snake { public partial class Main : Form { public Main() { InitializeComponent(); // Initialize ClientSize - measurements are in const // variables on class Board. this.ClientSize = new Size(Board.Width, Board.Height + Board.Unit + menuStrip.Height); // Initialize game status label statusLabel = new Label(); statusLabel.Font = new Font("Arial", 12); statusLabel.BackColor = Color.LightGray; statusLabel.AutoSize = true; statusLabel.Location = new Point(Board.Width * 1 / 24, Board.Height + Board.HalfUnit / 2 + menuStrip.Height); statusLabel.Text = "Press F2 to start a new game"; this.Controls.Add(statusLabel); // Initialize pizza counter label pizzaLabel = new Label(); pizzaLabel.Font = new Font("Arial", 12); pizzaLabel.BackColor = Color.LightGray; pizzaLabel.AutoSize = true; pizzaLabel.Location = new Point(Board.Width * 2 / 3, Board.Height + Board.HalfUnit / 2 + menuStrip.Height); pizzaLabel.Text = ""; this.Controls.Add(pizzaLabel); // Initilaize game time label timeLabel = new Label(); timeLabel.Font = new Font("Arial", 12); timeLabel.BackColor = Color.LightGray; timeLabel.AutoSize = true; timeLabel.Location = new Point(Board.Width * 5 / 6, Board.Height + Board.HalfUnit / 2 + menuStrip.Height); timeLabel.Text = ""; this.Controls.Add(timeLabel); // Initialize status area label statusArea = new Label(); statusArea.BackColor = Color.LightGray; statusArea.Size = new Size(Board.Width, Board.Unit); statusArea.Location = new Point(0, Board.Height + menuStrip.Height); this.Controls.Add(statusArea); // Subscribe method for game timer event, and set the interval myTimer.Tick += new EventHandler(myTimer_Tick); myTimer.Interval = 350; } private Random myRandom = new Random(); // Class Vertebra inherits from PictureBox // and represents a single snake link. private Vertebra myVertebra; // currently moved vertebra private Vertebra browseVertebra; // for browsing through vertebras private Vertebra newVertebra; // newely created vertebra // Class Pizza inherits from PictureBox // and represents the pizza sprite. private Pizza myPizza; // The statusArea Label serves as background // area for the three game status Labels. private Label statusArea, statusLabel, pizzaLabel, timeLabel; private int pizzaLocX, pizzaLocY; private Point nextHeadLocation, lastTailLocation, pizzaLocation; private int vertCount = 0, pizzaCount = -1; private enum Direction { Left, Right, Up, Down } private Direction myDirection; private enum GameState { None, Play, Grow, Pause, Over }; private GameState myGameState = GameState.None; // Please note that the game Timer is of // System.Windows.Forms.Timer class. private Timer myTimer = new Timer(); private int tickCount = 0, timeCount = 0; private XDocument highScoresDoc; // XML High Scores document used in LINQ to XML private string highScoresStr; // Property for getting the current // game state by Vertebra class. public string MyGameState { get { return myGameState.ToString(); } } // On KeyDown snake movement is determined, // and also the game pause / resume keys. private void Main_KeyDown(object sender, KeyEventArgs e) { if (myGameState == GameState.Pause) { ResumeGame(); } else if (myGameState == GameState.Play) { // Please not that the snake can't turn // in the opposite direction. if (e.KeyCode == Keys.Left && myDirection != Direction.Right) myDirection = Direction.Left; else if (e.KeyCode == Keys.Right && myDirection != Direction.Left) myDirection = Direction.Right; else if (e.KeyCode == Keys.Up && myDirection != Direction.Down) myDirection = Direction.Up; else if (e.KeyCode == Keys.Down && myDirection != Direction.Up) myDirection = Direction.Down; if (e.KeyCode == Keys.P) { PauseGame(); } } } // Starts a new game. Called by the New menu item. private void NewGame() { // If this isn't the first game played, // dispose of all previous game resources. if (myGameState != GameState.None) { myTimer.Stop(); for (int i = 1; i <= vertCount; i++) { browseVertebra = (Vertebra)this.Controls.Find("vert" + i.ToString(), false)[0]; browseVertebra.Dispose(); } vertCount = 0; myPizza.Dispose(); pizzaCount = -1; myGameState = GameState.None; tickCount = 0; timeCount = 0; } statusLabel.Text = "Press P to pause game"; pizzaLabel.Text = "0"; timeLabel.Text = "0"; myTimer.Start(); myDirection = (Direction)myRandom.Next(0, 3); // initial snake movement direction is random myGameState = GameState.Play; // Initialize first snake Vertebra myVertebra = new Vertebra(); myVertebra.Name = "vert1"; nextHeadLocation = new System.Drawing.Point((Board.Width - Board.Unit) / 2, (Board.Height - Board.Unit) / 2 + menuStrip.Height); myVertebra.Location = nextHeadLocation; this.Controls.Add(myVertebra); vertCount++; // Initialize the Pizza myPizza = new Pizza(); RelocatePizza(); this.Controls.Add(myPizza); } // Calculates the snake head location for the next move (nextHeadLocation), // and returns a boolean according to the move's validity. private bool NextMove() { if (myDirection == Direction.Left) nextHeadLocation = new Point(myVertebra.Location.X - Board.Unit, myVertebra.Location.Y); else if (myDirection == Direction.Right) nextHeadLocation = new Point(myVertebra.Location.X + Board.Unit, myVertebra.Location.Y); else if (myDirection == Direction.Up) nextHeadLocation = new Point(myVertebra.Location.X, myVertebra.Location.Y - Board.Unit); else if (myDirection == Direction.Down) nextHeadLocation = new Point(myVertebra.Location.X, myVertebra.Location.Y + Board.Unit); // check if location is outside the game board if (nextHeadLocation.X < 0 || nextHeadLocation.X >= Board.Width || nextHeadLocation.Y < menuStrip.Height || nextHeadLocation.Y >= Board.Height + menuStrip.Height) { return false; } // check if snake overlaps itself (only for over 4 vertebras) else if (vertCount > 4) { for (int i = 1; i < vertCount; i++) { browseVertebra = (Vertebra)this.Controls.Find("vert" + i.ToString(), false)[0]; if (browseVertebra.Location == nextHeadLocation) { return false; } } return true; } else { return true; } } // Executes the move calculated by NextMove method, // by placing the last Vertebra at nextHeadLocation. private void MakeMove() { // The vertebras are named as "vert" + position number from 1 to vertCount. myVertebra = (Vertebra)this.Controls.Find("vert" + vertCount.ToString(), false)[0]; // get the last Vertebra lastTailLocation = myVertebra.Location; // save its location, may be needed by a new Vertebra myVertebra.Name = "vert0"; // temporary rename as position 0 myVertebra.Location = nextHeadLocation; // move to nextHeadLocation // After the move is performed, position numbers in Vertebra names // are pushed one step up, to restore the 1 to vertCount numbering. for (int i = vertCount; i > 0; i--) { browseVertebra = (Vertebra)this.Controls.Find("vert" + (i - 1).ToString(), false)[0]; browseVertebra.Name = "vert" + i.ToString(); } // If the new location overlaps the Pizza, // relocate Pizza and place a new Vertebra at lastTailLocation. if (myVertebra.Location == pizzaLocation) { RelocatePizza(); newVertebra = new Vertebra(); vertCount++; newVertebra.Name = "vert" + vertCount.ToString(); newVertebra.Location = lastTailLocation; this.Controls.Add(newVertebra); } } // Relocates the Pizza at a random available location. // Called by the MakeMove method. private void RelocatePizza() { pizzaCount++; pizzaLabel.Text = pizzaCount.ToString() + " pizzas"; pizzaLocX = myRandom.Next(1, Board.UnitsOnX) * Board.Unit; pizzaLocY = myRandom.Next(1, Board.UnitsOnY) * Board.Unit + menuStrip.Height; pizzaLocation = new Point(pizzaLocX, pizzaLocY); // Check if the new random location overlaps with any Vertebra. // If so - this method recalls itself for a new random location. for (int i = 1; i <= vertCount; i++) { browseVertebra = (Vertebra)this.Controls.Find("vert" + i.ToString(), false)[0]; if (browseVertebra.Location == pizzaLocation) RelocatePizza(); } // If no overlaps were found, the Pizza is relocated. myPizza.Location = pizzaLocation; } // Subscribed by the game timer Tick event. private void myTimer_Tick(object source, EventArgs e) { // Update game time counter and label. tickCount++; timeCount = (int)(tickCount * myTimer.Interval / 1000); timeLabel.Text = timeCount.ToString() + " sec."; if (myGameState == GameState.Play) { if (NextMove() == true) // if next move is valid - proceed { MakeMove(); } else // game over { myTimer.Stop(); myGameState = GameState.Over; statusLabel.Text = "Game Over, press F2 to restart"; CheckScores(); } } } // Checks to enter the game in the high scores. // Called by timer Tick event handler when a game is over. private void CheckScores() { // If it doesn't exist - create the high scores xml file. if (!System.IO.File.Exists("SnakeHighScores.xml")) { CreateHighScoresDoc(); } highScoresDoc = XDocument.Load("SnakeHighScores.xml"); // Get the lowest score - the smallest amount of pizzas // in the longest game time. XElement lowestScore = highScoresDoc.Root.Element("Slot"); foreach (XElement browseSlot in highScoresDoc.Root.Elements()) { int browsePizzas = int.Parse(browseSlot.Element("Pizzas").Value); int browseTime = int.Parse(browseSlot.Element("Time").Value); int lowestPizzas = int.Parse(lowestScore.Element("Pizzas").Value); int lowestTime = int.Parse(lowestScore.Element("Time").Value); if ((browsePizzas < lowestPizzas) || (browsePizzas == lowestPizzas) && (browseTime > lowestTime)) { lowestScore = browseSlot; } } // If the game score is higher than the lowest score, // prompt the player for his name, replace that // high scores slot, and display the new scores. if ((int.Parse(lowestScore.Element("Pizzas").Value) < pizzaCount) || (int.Parse(lowestScore.Element("Pizzas").Value) == pizzaCount) && (int.Parse(lowestScore.Element("Time").Value) > timeCount)) { PlayerDialog MyPlayerDialog = new PlayerDialog(); if (MyPlayerDialog.ShowDialog() == DialogResult.OK) { lowestScore.Element("Player").SetValue(MyPlayerDialog.PlayerName); lowestScore.Element("Pizzas").SetValue(pizzaCount.ToString()); lowestScore.Element("Time").SetValue(timeCount); highScoresDoc.Save("SnakeHighScores.xml"); DisplayHighScores(); } } } // Creates a high scores xml file. private void CreateHighScoresDoc() { highScoresDoc = new XDocument( new XElement("HighScores") ); for (int i = 0; i < 10; i++) { highScoresDoc.Root.Add(new XElement("Slot", new XElement("Player", "-"), new XElement("Pizzas", "0"), new XElement("Time", "0") ) ); } highScoresDoc.Save("SnakeHighScores.xml"); } // Displays the high scores in a MessageBox. private void DisplayHighScores() { highScoresDoc = XDocument.Load("SnakeHighScores.xml"); var myHighScores = from mySlot in highScoresDoc.Root.Elements() orderby int.Parse(mySlot.Element("Pizzas").Value) descending, int.Parse(mySlot.Element("Time").Value) select new { player = mySlot.Element("Player").Value, pizzas = mySlot.Element("Pizzas").Value, time = mySlot.Element("Time").Value }; highScoresStr = "Player\tPizzas\tTime\n\n"; foreach (var myHighScore in myHighScores) { highScoresStr += myHighScore.player + "\t" + myHighScore.pizzas + "\t" + myHighScore.time + "\n"; } MessageBox.Show(highScoresStr, "Snake"); } // Method for the New menu item. private void newToolStripMenuItem_Click(object sender, EventArgs e) { // If a game is in progress, prompt the user about restarting a new game. if (myGameState == GameState.Play) { DialogResult result; result = MessageBox.Show("There is a game in progress.\nDo you want to restart?", "Snake", MessageBoxButtons.YesNo, MessageBoxIcon.Question, MessageBoxDefaultButton.Button2); if (result == DialogResult.Yes) { NewGame(); } } else { NewGame(); } } // Method for the High Scores menu item. private void highScoresToolStripMenuItem_Click(object sender, EventArgs e) { // If it doesn't exist - create the high scores xml file. if (!System.IO.File.Exists("SnakeHighScores.xml")) { CreateHighScoresDoc(); } DisplayHighScores(); } // Pauses a game - stops the game timer. private void PauseGame() { myTimer.Stop(); myGameState = GameState.Pause; statusLabel.Text = "Paused, press any key to resume"; } // Resumes a paused game - starts the game timer. private void ResumeGame() { myTimer.Start(); myGameState = GameState.Play; statusLabel.Text = "Press P to pause game"; } // On deactivation of the Main window, the game is paused. private void Main_Deactivate(object sender, EventArgs e) { if (myGameState == GameState.Play) { PauseGame(); } } // On activation of the game menu, the game is paused. private void menuStrip_MenuActivate(object sender, EventArgs e) { if (myGameState == GameState.Play) { PauseGame(); } } // Method for the Exit menu item. private void exitToolStripMenuItem_Click(object sender, EventArgs e) { this.Close(); } } }

Here is the code of the Vertebra Class: using System; using System.Collections.Generic; using System.Drawing; using System.Text; using System.Timers; namespace Snake { public class Vertebra : System.Windows.Forms.PictureBox { private Bitmap myImage; // Please note that the Vertebra Timer is of // System.Timers.Timer class. private Timer myTimer = new Timer(); private enum VertebraState { None, Born, Move, Dead }; private VertebraState myVertebraState = VertebraState.None; int i = 0; // for numbering animation steps public Vertebra() : base() { // Subscribe method for Vertebra timer event. myTimer.Elapsed += new ElapsedEventHandler(myTimer_Elapsed); this.Size = new Size(Board.Unit, Board.Unit); this.BackColor = Color.Transparent; myImage = new Bitmap(Board.Unit, Board.Unit); myTimer.Interval = 25; myTimer.Start(); myVertebraState = VertebraState.Born; } // Subscribed by the Vertebra timer Elapsed event. private void myTimer_Elapsed(object source, EventArgs e) { if (myVertebraState == VertebraState.Born) // when a Vertebra is created { DrawVertebra(Pens.BlueViolet, VertebraState.Move); } else if (((Main)this.Parent).MyGameState == "Over" && myVertebraState == VertebraState.Move) // when game is over { DrawVertebra(Pens.Gray, VertebraState.Dead); } } // Draws the growing squares animation with the requested Pen. // On finish, sets the requested myVertebraState. private void DrawVertebra(Pen myPen, VertebraState myNextState) { Graphics g = Graphics.FromImage(myImage); g.DrawRectangle(myPen, (myImage.Width - i) / 2, (myImage.Height - i) / 2, i, i); this.Image = myImage; i += 4; if (i >= Board.Unit) { myVertebraState = myNextState; i = 0; } } } }

And here are a couple of screenshots: