useMemo
is used to memoize the result of a computation, preventing expensive calculations on every render. It re-computes the memoized value only when one of the dependencies has changed.
import React, { useMemo } from 'react';
function ExpensiveCalculationComponent({ number }) {
const squaredNumber = useMemo(() => {
console.log('Calculating...');
return number * number;
}, [number]);
return <div>The square of {number} is {squaredNumber}</div>;
}