State Management · Junior · Question 3 of 75

When should you use the functional update `setCount(c => c + 1)` instead of `setCount(count + 1)`?

✓Correct answer: When the new value depends on the previous one, especially with several updates in a row
2Only in class components; function components don't support it
3When the state holds a string rather than a number

Explanation

count is a snapshot of the current render. Three setCount(count + 1) calls in one handler produce +1, while three setCount(c => c + 1) produce +3, because each updater receives the result of the previous one. It also protects against stale closures in timers and effects.

When should you use the functional update `setCount(c => c + 1)` instead of `setCount(count + 1)`?

Explanation

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When should you use the functional update setCount(c => c + 1) instead of setCount(count + 1)?

Explanation

Further reading

Test yourself

When should you use the functional update `setCount(c => c + 1)` instead of `setCount(count + 1)`?