Tutorial on how to create a shopping cart system in JavaScript.
Creating a shopping cart system in JavaScript involves several steps, including managing products, adding items to the cart, updating quantities, removing items, and calculating totals. Below is a basic tutorial to guide you through the process: ## <br>1. Set up HTML Structure: Start with a basic HTML structure containing elements for displaying products and the shopping cart. ```html <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Shopping Cart</title> </head> <body> <div id="products"> <!-- Product listings will be displayed here --> </div> <div id="cart"> <!-- Shopping cart details will be displayed here --> </div> <script src="script.js"></script> </body> </html> ``` ## <br>2. Define Products: In your JavaScript file (**script.js**), define an array of products with details like name, price, and quantity. ```js const products = [ { id: 1, name: 'Product 1', price: 10 }, { id: 2, name: 'Product 2', price: 15 }, { id: 3, name: 'Product 3', price: 20 }, // Add more products as needed ]; ``` ## <br>3. Display Products: Write a function to display products on the webpage. ```js function displayProducts() { const productsContainer = document.getElementById('products'); products.forEach(product => { const productElement = document.createElement('div'); productElement.innerHTML = ` <p>${product.name} - $${product.price}</p> <button onclick="addToCart(${product.id})">Add to Cart</button> `; productsContainer.appendChild(productElement); }); } ``` ## <br>4. Add Items to Cart: Implement a function to add items to the shopping cart. ```js let cart = []; function addToCart(productId) { const product = products.find(p => p.id === productId); cart.push({...product, quantity: 1}); updateCart(); } ``` ## <br>5. Update Cart: Write a function to update the cart display. ```js function updateCart() { const cartContainer = document.getElementById('cart'); cartContainer.innerHTML = ''; let total = 0; cart.forEach(item => { const itemElement = document.createElement('div'); itemElement.innerHTML = ` <p>${item.name} - $${item.price} - Quantity: ${item.quantity}</p> <button onclick="removeFromCart(${item.id})">Remove</button> `; cartContainer.appendChild(itemElement); total += item.price * item.quantity; }); cartContainer.innerHTML += `<p>Total: $${total}</p>`; } ``` ## <br>6. Remove Items from Cart: Implement a function to remove items from the cart. ```js function removeFromCart(productId) { const index = cart.findIndex(item => item.id === productId); if (index !== -1) { cart.splice(index, 1); updateCart(); } } ``` ## <br>7. Initialize: Call the displayProducts() function to initialize the product display. ```js displayProducts(); ``` This is a basic implementation. You can enhance it by adding features like quantity adjustment, item duplication prevention, localStorage for persistence, and a checkout process. Add these features and let me know in the comments how it turns out.