What are controlled vs uncontrolled components?

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⚖️ Controlled vs Uncontrolled Components in React

In React, form inputs like <input>, <textarea>, and <select> can be controlled or uncontrolled, based on how their values are managed.

✅ Controlled Components

In controlled components, React controls the form data using state.

The input’s value is tied to a state variable.

Updates happen through onChange handlers.

Example

jsx

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

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

🔹 Benefits:

Easy to validate input

Full control over form behavior

Predictable data flow

✅ Uncontrolled Components

In uncontrolled components, the DOM controls the form data.

You use a ref to access the input value directly.

React doesn’t track input state.

Example:

jsx

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const inputRef = useRef();

<input ref={inputRef} />

// Access with inputRef.current.value

🔹 Benefits:

Less code for simple forms

Slightly better performance in large forms

🧠 Key Differences:

Feature                 Controlled        Uncontrolled

Data Handling      React State         DOM (via ref)

Validation         Easy to implement   Manual

Use Case           Complex forms Simple, quick forms

✅ Summary:

Use controlled components when you need full control and validation. Use uncontrolled components for simpler tasks or when integrating with non-React code.

Let me know if you'd like a visual version for a slide or post!

Read more: 

What are React Hooks? Name a few.

How do you conditionally render components?

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