Course Chapters
Chapter 7

State Management & React Hooks

Learn how to create interactive and dynamic applications using React Hooks.

🧠 What is State?

State is data that changes inside a component. When state changes, React automatically updates the UI.

const [count, setCount] = useState(0);

⚡ useState Hook

useState allows components to store and update dynamic values.

const [count, setCount] = useState(0);

setCount(count + 1);
Count: 0

🔄 Toggle State Example

State is commonly used for opening modals, menus, and dropdowns.

const [isOpen, setIsOpen] = useState(false);

setIsOpen(!isOpen);

🧩 useEffect Hook

useEffect runs side effects like API calls, timers, or event listeners.

useEffect(() => {
  console.log("Component Mounted");
}, []);
Open browser console to see the effect message.

📝 Handling User Input

Forms use state to store input values.

const [name, setName] = useState("");

<input
  value={name}
  onChange={(e) => setName(e.target.value)}
/>
Hello, Guest 👋

✅ Best Practices

Keep State Minimal

Only store values that actually change.

Use useEffect Carefully

Avoid unnecessary effects to improve performance.

Split Complex UI

Break large interactive sections into smaller reusable components.

🧠 Summary

React Hooks make applications interactive and dynamic. State controls changing data, while effects handle side actions like API calls and events.

🎯 Pro Tip

Most modern React applications are built using hooks. Mastering useState and useEffect is essential for becoming a strong frontend developer.