How to Code Tic-Tac-Toe Game in HTML, CSS and JavaScript

In this video tutorial, we will be coding a tic tac toe game using HTML, JavaScript & CSS. We will begin by creating the tic tac toe grid with html & css. We will use JavaScript in an object orientated style to create the tic tac toe game.

Source Code:

HTML File

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <link rel="stylesheet" href="style.css">
  <title>Document</title>
</head>
<body>
  <div class="container">
    <h1>Tic Tac Toe</h1>
    <div class="row border-b">
      <div class="col border-r"></div>
      <div class="col border-r"></div>
      <div class="col"></div>
    </div>
    <div class="row border-b">
      <div class="col border-r"></div>
      <div class="col border-r"></div>
      <div class="col"></div>
    </div>
    <div class="row">
      <div class="col border-r"></div>
      <div class="col border-r"></div>
      <div class="col"></div>
    </div>
  </div>
  <script src="script.js"></script>
</body>
</html>

CSS File:

.container {
  width: 320px;
  height: 320px;
  margin: auto;
  margin-top: 100px;
}

.container h1 {
  text-align: center;
  font-size: 50px;
}

.row {
  height: 100px;
}

.col {
  height: 100px;
  width: 100px;
  float: left;
  font-size: 100px;
  text-align: center;
  line-height: 100px;
}

.col:hover {
    background-color: lightgray;
}

.border-b {
  border-bottom: 10px solid black;
}

.border-r {
  border-right: 10px solid black;
}

.winner {
    color: blue;
}

JavaScript File:

const ticTacToeGame = new TicTacToeGame();
ticTacToeGame.start();

function TicTacToeGame() {
  const board = new Board();
  const humanPlayer = new HumanPlayer(board);
  const computerPlayer = new ComputerPlayer(board);
  let turn = 0;

  this.start = function() {
    const config = { childList: true };
    const observer = new MutationObserver(() => takeTurn());
    board.positions.forEach((el) => observer.observe(el, config));
    takeTurn();
  }

  function takeTurn() {
    if (board.checkForWinner()) {
      return;
    }

    if (turn % 2 === 0) {
      humanPlayer.takeTurn();
    } else {
      computerPlayer.takeTurn();
    }

    turn++;
  };
}

function Board() {
  this.positions = Array.from(document.querySelectorAll('.col'));

  this.checkForWinner = function() {
    let winner = false;

    const winningCombinations = [
        [0,1,2],
        [3,4,5],
        [6,7,8],
        [0,4,8],
        [2,4,6],
        [0,3,6],
        [1,4,7],
        [2,5,8]
    ];

    const positions = this.positions;
    winningCombinations.forEach((winningCombo) => {
      const pos0InnerText = positions[winningCombo[0]].innerText;
      const pos1InnerText = positions[winningCombo[1]].innerText;
      const pos2InnerText = positions[winningCombo[2]].innerText;
      const isWinningCombo = pos0InnerText !== '' &&
        pos0InnerText === pos1InnerText && pos1InnerText === pos2InnerText;
      if (isWinningCombo) {
          winner = true;
          winningCombo.forEach((index) => {
            positions[index].className += ' winner';
          })
      }
    });

    return winner;
  }
}

function ComputerPlayer(board) {
  this.takeTurn = function() {
    let availablePositions = board.positions.filter((p) => p.innerText === '');
    const move = Math.floor(Math.random() * (availablePositions.length - 0));
    availablePositions[move].innerText = 'O';
  }
}

function HumanPlayer(board) {
  this.takeTurn = function() {
    board.positions.forEach(el =>
      el.addEventListener('click', handleTurnTaken));
  }

  function handleTurnTaken(event) {
    event.target.innerText = 'X';
    board.positions
      .forEach(el => el.removeEventListener('click', handleTurnTaken));
  }
}

Tic Tac Toe Code: https://github.com/kriscfoster/Tic-Tac-Toe-Game

Subscribe: https://www.youtube.com/@KrisFoster1/featured

#javascript #html #css #web-development #game-development