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)

Dispatching states

In this chapter, we have learned that the dispatch function, provided by the useState hook, allows us to request a change of state any time we want to. The input argument that represents an action can be a string, a number, an object, an array, or any JavaScript expression:

  dispatch({ state })
  dispatch([ state ])

We know that, internally, the input argument supports a functional update format as well:

  dispatch(state => state + 1)

The benefit of using a functional update format here is that it has an opportunity to read the previous state before making a move toward the next state. This sometimes becomes useful if you build a new state that requires an old state.

A dispatched state is compared with the current state before making a final call if it changes. This means that not all dispatches end up with a state change. Take the following code as an example...