Q1. What are the main components of an e-commerce cart?
Typically, you have a ProductList, ProductItem, Cart, CartItem, and possibly a Checkout component. State manages products, cart items, and total price.
Q2. How do you manage cart state?
You can use useState or useReducer with an array of items. Each item has id, name, price, quantity. Functions: addToCart, removeFromCart, updateQuantity. Use context or Redux for global access.
Q3. How do you calculate the total price?
Use a derived value: reduce over cart items to sum price * quantity. This can be computed in the render or memoized with useMemo.
Q4. How do you handle adding items to cart?
When user clicks "Add to Cart", check if item already exists. If yes, increase quantity; else, add new item with quantity 1. Update state accordingly.
Q5. How can you persist cart across sessions?
Use localStorage to save cart items. On app load, initialize cart from localStorage. Update localStorage in useEffect whenever cart changes.