How to Use the useMemo React Hook

In the world of React, one hook that can come in handy is useMemo.

import React, { useMemo } from 'react';

The useMemo hook allows you to create a memoized value.

This hook is similar to useCallback, but with a few differences. While useCallback returns a memoized callback, useMemo returns a memoized value, which is the result of a function call. Additionally, the use case for these two hooks is different. useCallback is typically used for callbacks passed to child components.

Sometimes, you might need to compute a value that involves complex calculations, querying a database, or making a network request. By using the useMemo hook, this operation is only performed once. The resulting value is then stored in a memoized value, allowing for faster access in subsequent references.

Here is an example of how to use the hook:

const memoizedValue = useMemo(() => expensiveOperation(), []);

Make sure to provide an empty array as the second parameter to useMemo. This is important for enabling memoization. If you need to pass arguments, include them in the array:

const memoizedValue = useMemo(() => expensiveOperation(param1, param2), [param1, param2]);

If any of the parameters change when accessing the value, the value will be recalculated without memoization.