Learn React Hooks for Frontend Development/

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Understanding the useMemo Design

Understanding the useMemo Design

Learn about the fundamental concept of the useMemo hook in React, a powerful tool designed to optimize value assignments within function components.

We'll cover the following...

Introduction to the useMemo hook

React adds a useMemo hook that allows us to reuse the previous assignment in an update.

React provides a useMemo hook to support a value assignment through a function that can either return a new value or an old value from the previous update:

const Title = () => {
  const label = useMemo(() => {
    return "Hello World"
  }, [])
}
Using useMemo to memoize the constant label "Hello World"

The useMemo workflow summary

Let's understand this from a higher level, the following diagram outlines the useMemo hook in terms of the effects workflow in React (see the image below):

useMemo workflow
useMemo workflow

Compared to useState and useEffect, useMemo is quite straightforward. ...