701. React Effect Cleanup Order

Easy•

Select the best answer.

function Demo(props) {
  React.useEffect(() => {
    console.log("subscribe", props.id);
    return () => console.log("cleanup", props.id);
  }, [props.id]);
  return null;
}

When id changes from 1 to 2, what runs first?

subscribe 2both at same timecleanup 1nothing

Select an option and submit your answer.

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701. React Effect Cleanup Order

Easy•

Select the best answer.

function Demo(props) {
  React.useEffect(() => {
    console.log("subscribe", props.id);
    return () => console.log("cleanup", props.id);
  }, [props.id]);
  return null;
}

When id changes from 1 to 2, what runs first?

subscribe 2both at same timecleanup 1nothing

Select an option and submit your answer.

Next ProblemAuto-advance on correct answer