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JavaScript IIFE Block and Callback
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Create Tic Tac toe with JavaScript (Free Code)

Do you want to make a Simple Tic-Tac-Toe game using JavaScript?

In this article you will learn how to create tic tac toe game using html css and javascript. If you are a beginner in JavaScript then Tic Tac Toe Game is perfect for you. This simple javascript game will help you improve your knowledge of javascript.

Create Tic Tac Toe with JavaScript

Earlier I shared another Simple Tic-Tac-Toe JavaScript game for beginners. So I made this design in a very advanced way. Here basically we will play with the computer that is we will play with the computer.

To create this tic-tac-toe javascript first I created the basic structure by html. Then I designed it with css and finally activated this project (tic tac toe javascript code against computer) with javascript.

Tic-tac-toe Game in JavaScript

JavaScript Tic Tac Toe is a simple game where two players take turns marking a grid of 3×3 squares, typically using X and O symbols. JavaScript is a programming language that can be used to create interactive websites and games, such as a Tic Tac Toe game.

A JavaScript implementation of Tic Tac Toe would involve creating a grid of squares using HTML and CSS, and then using JavaScript to handle the logic of the game, including determining the winner and allowing players to take turns.

As you can see above this is an advanced Tic Tac Toe game that I made with javascript. Like a normal JavaScript Tic Tac Toe game, there are 9 cells and two symbols.

Here I have defined symbol “0” for user and “X” for computer. But you can change it if you want. When you click in any one of those 9 cells, another cell will automatically be filled by the computer.

Besides, I have added different types of color FF in the project (tic tac toe javascript code against computer) to make this design more modern.

How to make tic tac toe in HTML CSS and JavaScript

Now if you want to build it then you can follow the tutorial below. I have explained the complete codes step by step keeping the beginners in mind.

Hope you know the rules of this game. It is a simple javascript game where two players take turns marking the spaces in a 3×3 grid with X’s and O’s, with the goal of getting three of their marks in a row, either horizontally, vertically, or diagonally. The player who succeeds in placing three of their marks in a row is the winner.

Step 1: Basic structure of Tic Tac Toe game

First I created a basic structure of this project using the following HTML and CSS codes. Besides, I have added a heading here mainly to enhance the beauty. This heading is created by H1 tag in HTML. 

<div class="container">

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: Arial, Helvetica, sans-serif;

.container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: #eee;

h1 {
  font-size: 4rem;
  margin-bottom: 0.5em;

Basic structure of Tic Tac Toe game

Step 2: Create a place to play Tic Tac Toe games

Now create a small area for this tic tac toe javascript. Within this box are nine smaller boxes into which players can input their symbols. Also we designed this area by some css.

<div class="play-area">

.play-area {
  display: grid;
  box-shadow: 0 0 20px rgba(0,139,253,0.25);
  grid-template-columns: auto auto auto;
  background-color: #fff;
  padding: 20px;

Create a place to play Tic Tac Toe games

Step 3: Results of the JavaScript Tic Tac Toe game

Now another heading we need to create is within this project(How to Build Tic Tac Toe with JavaScript, HTML and CSS). This heading is mainly for showing results. 

Although this heading is currently not visible to us because there is no information in the heading. We will add this information via javascript. Results will be available automatically after Tic Tac Toe game is over.

<h2 id="winner"></h2>
h2 {
  margin-top: 1em;
  font-size: 2rem;
  margin-bottom: 0.5em;

Step 4: Create the game's restart button

Now we have to create a button in this simple Tic-Tac-Toe game. This button will basically work as a reset button. When you click on this button, the game will restart from a new state.

<button onclick="reset_board()">RESET</button>
button {
  outline: none;
  background: rgb(8, 88, 208);
  padding: 12px 40px;
  font-size: 1rem;
  font-weight: bold;
  color: #fff;
  border: none;
  transition: all 0.2s ease-in-out;

button:hover {
  cursor: pointer;
  background: green;
  color: white;

Results of the JavaScript Tic Tac Toe game

Step 5: Activate Simple Tic-Tac-Toe with JavaScript

Above we have designed this project(How to create a tic tac toe grid in JavaScript?). Now it’s time to make it work using JavaScript. We have used quite a bit of JavaScript code to make this game work. But don’t worry I will tell you all the codes step by step.

const player = "O";
const computer = "X";

let board_full = false;
let play_board = ["", "", "", "", "", "", "", "", ""];

const board_container = document.querySelector(".play-area");
const winner_statement = document.getElementById("winner");

With these variables, you’ve defined the player and computer as “O” and “X” respectively, and created an empty board to play on. The board_full variable will be used to check if the board is full and the game is over, and the play_board array will hold the state of the game. 

The board_container variable is used to select the element on the page where the Tic Tac Toe board will be rendered, and the winner_statement variable is used to select the element where the winner statement will be displayed.

check_board_complete = () => {
  let flag = true;
  play_board.forEach(element => {
    if (element != player && element != computer) {
      flag = false;
  board_full = flag;

The function is using the forEach() method to iterate over the play_board array, and it checks if each element is not equal to the player or computer. If any element is not equal to the player or computer, it sets the flag variable to false and breaks out of the loop. 

If the loop completes and the flag variable is still true, it means that all the elements are equal to the player or computer, and the board is full. Then the board_full variable is updated to reflect that the board is full.

You can use this function at the end of the player’s turn and computer’s turn, to check if the board is full and the game is over.

const check_line = (a, b, c) => {
  return (
    play_board[a] == play_board[b] &&
    play_board[b] == play_board[c] &&
    (play_board[a] == player || play_board[a] == computer)

The function takes in 3 arguments, a, b, c, which represent the indices of the 3 cells on the board that need to be checked for a winning line.

The function uses the ternary operator to check if the values at the indices a, b, c in the play_board array are the same and not empty. If the values are the same and not empty, the function returns true, otherwise it returns false.

You can use this function in a larger function that checks for all the possible winning combinations on the board.

const check_match = () => {
  for (i = 0; i < 9; i += 3) {
    if (check_line(i, i + 1, i + 2)) {
      document.querySelector(`#block_${i + 1}`).classList.add("win");
      document.querySelector(`#block_${i + 2}`).classList.add("win");
      return play_board[i];
  for (i = 0; i < 3; i++) {
    if (check_line(i, i + 3, i + 6)) {
      document.querySelector(`#block_${i + 3}`).classList.add("win");
      document.querySelector(`#block_${i + 6}`).classList.add("win");
      return play_board[i];
  if (check_line(0, 4, 8)) {
    return play_board[0];
  if (check_line(2, 4, 6)) {
    return play_board[2];
  return "";

The check_match() function uses two for loops to check for all the possible winning combinations on the board, both horizontally and vertically. It also includes two if statements to check for the two diagonal winning combinations.

The function uses the check_line function you created earlier to check if a line is a winning line. If a winning line is found, the function highlights the winning cells by adding the “win” class to them. This class can be used in your CSS to change the appearance of the winning cells, for example by adding a different background color.

The function also returns the value of the first cell in the winning line, which should be either “X” or “O” depending on who won the game.

You can use this function in another function that checks for a win or a draw and updates the UI accordingly.

const check_for_winner = () => {
  let res = check_match()
  if (res == player) {
    winner.innerText = "Winner is player!!";
    board_full = true
  } else if (res == computer) {
    winner.innerText = "Winner is computer";
    board_full = true
  } else if (board_full) {
    winner.innerText = "Draw!";

This code looks like it’s checking for a winner in a javascript Tic Tac Toe game. The check_line function takes in 3 indices of the play_board array and checks if the values at those indices are equal to each other and if they are equal to either the player or computer. 

The check_match function uses the check_line function to check for a winner across the rows, columns, and diagonals of the Tic Tac Toe board. If a winning line is found, the check_match function adds a “win” class to the corresponding HTML elements of the Tic Tac Toe board and returns the winning player. 

The check_for_winner function calls the check_match function and checks the returned value. If the returned value is the player, it sets the winner statement to “Winner is player!!” and adds playerWin class.

const render_board = () => {
  board_container.innerHTML = ""
  play_board.forEach((e, i) => {
    board_container.innerHTML += `<div id="block_${i}" class="block" onclick="addPlayerMove(${i})">${play_board[i]}</div>`
    if (e == player || e == computer) {

The render_board() function creates a grid of divs in the HTML, each one representing a cell in the Tic-Tac-Toe board. The addPlayerMove() function allows the player to make a move by clicking on a cell in the grid. 

The check_board_complete() function checks if the board is full and the check_for_winner() function checks for a winner or draw. It also uses the check_match() function to check if any winning combination is formed.

const game_loop = () => {

The game_loop function combines all of these functions together to create the game loop that updates the game state and renders the game board to the user. 

It calls the render_board function to render the current state of the game board to the user, check_board_complete to check if the board is full and check_for_winner which checks if there is a winner or a draw, and updates the UI accordingly.

const addPlayerMove = e => {
  if (!board_full && play_board[e] == "") {
    play_board[e] = player;

The above code defines a Tic Tac Toe game in JavaScript that uses HTML and CSS for the game board and styling. The game’s state is maintained in the play_board array, and the game_loop function updates the state of the game, renders the board, and checks for a winner. 

The addPlayerMove function allows players to make a move by clicking on a block on the board, and the addComputerMove function allows the computer to make a move. The check_match, check_for_winner, render_board functions are also defined and used in the game loop to check for a winner or a draw, render the board and check if the game is complete.

const addComputerMove = () => {
  if (!board_full) {
    do {
      selected = Math.floor(Math.random() * 9);
    } while (play_board[selected] != "");
    play_board[selected] = computer;

Great! Your code is now complete and should be able to run a game of javascript Tic-Tac-Toe between a player and the computer. The player can make moves by clicking on the blocks on the game board, and the computer will randomly select an available space to make its move. The code also checks for a winner or a draw after each move, and updates the game board and the winner statement accordingly.

const reset_board = () => {
  play_board = ["", "", "", "", "", "", "", "", ""];
  board_full = false;
  winner.innerText = "";

This code defines a function called “reset_board” that sets the play_board array back to an empty array, sets the board_full variable to false, removes any classes related to winning or drawing from the winner element, sets the inner text of the winner element to an empty string, and then calls the render_board function to update the display. This function is likely intended to be used as a way to clear the game board and start a new game.

//initial render

That’s it, you have created a complete Tic-Tac-Toe game using JavaScript. To start the game, the player can click on any of the empty blocks on the board and the computer will automatically make its move. 

The game checks for a winner or a draw after each move and updates the board accordingly. The game can also be reset by calling the reset_board() function.

Step 6: Basic design of simple Tic-Tac-Toe game with CSS

Above we enabled Tic-tac-toe in JavaScript by JavaScript. Now we need to design it with some more CSS. We know there are 9 small boxes in this game that are currently too small for us to see. So a fixed size must be defined for each box.

.block {
  display: flex;
  width: 100px;
  height: 100px;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  font-weight: bold;
  border: 3px solid black;
  transition: background 0.2s ease-in-out;

.block:hover {
  cursor: pointer;
  background: #0ff30f;

.occupied:hover {
  background: #ff3a3a;

.win {
  background: #0ff30f;

.win:hover {
  background: #0ff30f;

Activate Simple Tic-Tac-Toe with JavaScript

As we can see in the above image there are 9 boxes created. But we want to hide some borders here. We will use the following CSS to hide those borders.

#block_2 {
  border-top: none;

#block_6 {
  border-left: none;

#block_8 {
  border-bottom: none;

#block_8 {
  border-right: none;
.playerWin {
  color: green;

.computerWin {
  color: red;

.draw {
  color: orangered;

We’ll make this project(Create a Tic-Tac-Toe with HTML and JavaScript) responsive  using a small amount of our own code. Here for Responsive only headings have been resized or reduced.

@media only screen and (max-width: 600px) {

  h1 {
    font-size: 3rem;
    margin-bottom: 0.5em;

  h2 {
    margin-top: 1em;
    font-size: 1.3rem;

Create Tic Tac Toe with JavaScript

Hope from this tutorial you got to know how I made this Simple Tic-Tac-Toe JavaScript game.

Not only this but earlier I have shared more advanced game tutorials. Earlier I shared another JavaScript Tic-Tac-Toe which is basically made by Simple Code. Where you can play with two users rather than with the computer. Be sure to comment how you like this project(How to Recreate Tic-Tac-Toe in Vanilla JavaScript).

Original article source at:


Jeromy  Lowe

Jeromy Lowe


Intro to Callback in JavaScript

During my journey of learning JavaScript and a few days in with React, I had to come to terms with callback functions. It was impossible to avoid its existence and blindly using it without understanding. To understand callback function we have to know a bit about functions. Here I want to talk about function expression, arrow function, and callback function.

What is a Callback function?

According to MDN doc:

A callback function is a function passed into another function as an argument, which is then invoked inside the outer function to complete some kind of routine or action.

In JavaScript, functions are objects, which means, like any other objects it can be assigned to a variable and passed as an argument to another function. In a nutshell, a callback function is a function that is provided as a parameter for other methods such as forEach method or addEventListener method and gets invoked at a certain point in time.

Passing functions as arguments

So how do we do this? Let’s see with an example below:


//whoAmI Function Declaration(Function Statement)
function whoAmI(event){

We attached the ‘click’ event listener to document with whoAmI function as a parameter that logs the tag name of the clicked target. Whenever ‘click’ happens whoAmI function will be called with an _event_ argument. We call whoAmI a callback function.

When we call a function by its name followed by ( ), we are telling the function to execute its code. When we name a function or pass a function without the ( ), the function does not execute.** The callback function doesn’t execute right away. Instead, the addEventListener method executes the function when the event occurs.**

One more thing I want to mention is because we used function declaration, we were able to call thewhoAmI function before it was declared. It’s the magic of hoisting in JS. But with function expression, it doesn’t get hoisted. So the order of writing function expressions and using them as callback would be crucial.

#callback #javascript #callback-function #function #javascript-fundamental

Rahul Jangid


What is JavaScript - Stackfindover - Blog

Who invented JavaScript, how it works, as we have given information about Programming language in our previous article ( What is PHP ), but today we will talk about what is JavaScript, why JavaScript is used The Answers to all such questions and much other information about JavaScript, you are going to get here today. Hope this information will work for you.

Who invented JavaScript?

JavaScript language was invented by Brendan Eich in 1995. JavaScript is inspired by Java Programming Language. The first name of JavaScript was Mocha which was named by Marc Andreessen, Marc Andreessen is the founder of Netscape and in the same year Mocha was renamed LiveScript, and later in December 1995, it was renamed JavaScript which is still in trend.

What is JavaScript?

JavaScript is a client-side scripting language used with HTML (Hypertext Markup Language). JavaScript is an Interpreted / Oriented language called JS in programming language JavaScript code can be run on any normal web browser. To run the code of JavaScript, we have to enable JavaScript of Web Browser. But some web browsers already have JavaScript enabled.

Today almost all websites are using it as web technology, mind is that there is maximum scope in JavaScript in the coming time, so if you want to become a programmer, then you can be very beneficial to learn JavaScript.

JavaScript Hello World Program

In JavaScript, ‘document.write‘ is used to represent a string on a browser.

<script type="text/javascript">
	document.write("Hello World!");

How to comment JavaScript code?

  • For single line comment in JavaScript we have to use // (double slashes)
  • For multiple line comments we have to use / * – – * /
<script type="text/javascript">

//single line comment

/* document.write("Hello"); */


Advantages and Disadvantages of JavaScript

#javascript #javascript code #javascript hello world #what is javascript #who invented javascript

Hire Dedicated JavaScript Developers -Hire JavaScript Developers

It is said that a digital resource a business has must be interactive in nature, so the website or the business app should be interactive. How do you make the app interactive? With the use of JavaScript.

Does your business need an interactive website or app?

Hire Dedicated JavaScript Developer from WebClues Infotech as the developer we offer is highly skilled and expert in what they do. Our developers are collaborative in nature and work with complete transparency with the customers.

The technology used to develop the overall app by the developers from WebClues Infotech is at par with the latest available technology.

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Niraj Kafle


The essential JavaScript concepts that you should understand

As a JavaScript developer of any level, you need to understand its foundational concepts and some of the new ideas that help us developing code. In this article, we are going to review 16 basic concepts. So without further ado, let’s get to it.

#javascript-interview #javascript-development #javascript-fundamental #javascript #javascript-tips