How Do You Code Blackjack in Javascript?

Blackjack is an incredibly popular card game that has been played by millions of people around the world. For those who are interested in learning how to code Blackjack in Javascript, this tutorial is for you!

Before we dive into the coding process, it’s important to understand the basic rules of Blackjack. In this game, the goal is to have a hand that totals 21 or as close to 21 as possible without going over.

Each player is dealt two cards and can choose to “hit” (receive another card) or “stand” (keep their current hand). The dealer also receives two cards and must hit until their hand reaches a total of 17 or higher.

Now that we have a basic understanding of the game, let’s start coding! The first step is to create a deck of cards using arrays. We can do this by creating an array for each suit (hearts, diamonds, clubs, spades) and then adding all of the card values (Ace through King) to each array.

Once we have our deck created, we need to shuffle it so that the cards are dealt randomly. We can use the Fisher-Yates shuffle algorithm for this:

“`javascript
function shuffle(array) {
var currentIndex = array.length,
temporaryValue,
randomIndex;

while (0 !== currentIndex) {

randomIndex = Math.floor(Math.random() * currentIndex);
currentIndex -= 1;

temporaryValue = array[currentIndex];
array[currentIndex] = array[randomIndex];
array[randomIndex] = temporaryValue;
}

return array;
}
“`

Now that our deck is shuffled, we can deal two cards to each player (including the dealer). To do this, we’ll create an array for each player’s hand and use a loop to add two cards from the deck to each hand:

“`javascript
var playerHand = [];
var dealerHand = [];

for (var i = 0; i < 2; i++) {
playerHand.push(deck.pop());
dealerHand.pop());
}
“`

Next, we need to create a function that will calculate the total value of each player's hand. Aces can be worth either 1 or 11, so we'll need to account for that in our calculation.

We can do this by looping through each card in the hand and adding its value to a variable called "total". If an Ace is found, we'll add 11 to the total unless it would cause the player to bust (go over 21), in which case we'll add 1 instead:

“`javascript
function calculateHand(hand) {
var total = 0;
var hasAce = false;

for (var i = 0; i < hand.length; i++) {
var cardValue = getCardValue(hand[i]);

if (cardValue === 1) {
hasAce = true;
}

total += cardValue;
}

if (hasAce && total + 10 21) {
// Player busts
endGame(false);
} else if (playerTotal === 21) {
// Player gets Blackjack
endGame(true);
} else {
// Game continues
showPlayerHand();
}
}

function playerStand() {
dealerTurn();
}
“`

Finally, we need to create a function for the dealer’s turn. The dealer must continue hitting until their hand totals 17 or higher. Once their hand is complete, we can compare it to each player’s hand and determine who wins:

“`javascript
function dealerTurn() {
var dealerTotal = calculateHand(dealerHand);

while (dealerTotal 21) {
// Dealer busts
endGame(true);
} else {
// Compare hands
var playerTotal = calculateHand(playerHand);

if (playerTotal > dealerTotal) {
endGame(true);
} else if (playerTotal < dealerTotal) {
endGame(false);
} else {
endGame(null); // Tie game
}
}
}

function endGame(playerWins) {
// Display winner and reset game
}
“`

And there you have it! With these functions in place, you now have a fully functioning Blackjack game in Javascript.

Of course, this is just a basic example and there are many ways to customize and improve upon the code. You could add features like splitting, doubling down, or insurance bets. You could also work on improving the user interface by adding graphics and animations.

But regardless of what direction you take your Blackjack game in, this tutorial should give you a solid foundation to build upon. Happy coding!