React · Middle · Question 14 of 75

What's the right way to get `fullName` from `firstName` and `lastName` stored in state?

1A separate fullName state and a useEffect that updates it
✓Correct answer: Compute it during render: const fullName = firstName + ' ' + lastName
3Keep fullName in a useRef and update it manually

Explanation

Values that can be computed from props and state shouldn't be stored in state. The "state + syncing effect" combo causes an extra render with a stale value and a risk of desync. If the computation is expensive, wrap it in useMemo.

What's the right way to get `fullName` from `firstName` and `lastName` stored in state?

Explanation

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What's the right way to get fullName from firstName and lastName stored in state?

Explanation

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Test yourself

What's the right way to get `fullName` from `firstName` and `lastName` stored in state?