Book Image

Designing React Hooks the Right Way

By : Fang Jin
Book Image

Designing React Hooks the Right Way

By: Fang Jin

Overview of this book

React hook creates a unique solution for using states in function components to orchestrate UI communication. They provide you with an easy interface to write custom data management solutions with low development and maintenance costs. Understanding how Hooks are designed enables you to use them more effectively, and this book helps you to do just that. This book starts with a custom-crafted solution to reveal why Hooks are needed in the first place. You will learn about the React engine and discover how each built-in Hook can manage a persistent value by hooking into it. You will walk through the design and implementation of each hook with code so that you gain a solid understanding. Finally, you'll get to grips with each Hook's pitfalls and find out how to effectively overcome them. By the end of this React book, you'll have gained the confidence to build and write Hooks for developing functional and efficient web applications at scale.
Table of Contents (12 chapters)

Chapter 6: Use Memo to Boost Performance

In the previous chapter, we learned how the useEffect hook is designed and how to use it to manage a side effect in React. In this chapter, we will change to an optimization topic for reusing the last assignment. We will first introduce how we can run into performance degradation in a typical web application. Then, we will walk through the design and source code behind useMemo and describe various ways of reusing a value conditionally. We'll then apply the optimization technique to two common cases: clicking to search and debouncing the search. At the end, the chapter also includes two bonus topics in the Appendix section, Not a Classical Memorization and Skipping a Child Update.

We will cover the following main topics in this chapter:

  • Performance degradation
  • Understanding the useMemo design
  • Reusing a last assignment
  • Test-Driving useMemo
  • useMemo examples
  • Questions and answers
  • Appendix