React Essentials · Forms & Events · Lesson 13 of 26
Controlled Inputs
Concept
Controlled Inputs
A controlled input's value is driven by React state, so state and the UI always stay in sync.
By the end of this lesson
- Explain the core idea behind Controlled Inputs.
- Predict output before running a change.
- Test one realistic and one unusual input.
- Use the result to make the next decision.
How to study this page
- 1. Read one concept.
- 2. Change the example.
- 3. Run, compare, and explain.
- 4. Complete the challenge below.
ExampleRunnable
const [name, setName] = useState("");
<input value={name} onChange={(e) => setName(e.target.value)} />;Self-check before continuing
Without looking at the example, describe what changes when you modify one input in Controlled Inputs. Then reopen the editor and prove your explanation with a small test.
You are ready to continue when you can predict, test, and explain the result.
Your turn
Build a controlled input that shows a live character count.
Loading editor…
Console