Book Image

Learn React with TypeScript - Second Edition

By : Carl Rippon
4.4 (8)
Book Image

Learn React with TypeScript - Second Edition

4.4 (8)
By: Carl Rippon

Overview of this book

Reading, navigating, and debugging a large frontend codebase is a major issue faced by frontend developers. This book is designed to help web developers like you learn about ReactJS and TypeScript, both of which power large-scale apps for many organizations. This second edition of Learn React with TypeScript is updated, enhanced, and improved to cover new features of React 18 including hooks, state management libraries, and features of TypeScript 4. The book will enable you to create well-structured and reusable React components that are easy to read and maintain, leveraging modern design patterns. You’ll be able to ensure that all your components are type-safe, making the most of TypeScript features, including some advanced types. You’ll also learn how to manage complex states using Redux and how to interact with a GraphQL web API. Finally, you’ll discover how to write robust unit tests for React components using Jest. By the end of the book, you’ll be well-equipped to use both React and TypeScript.
Table of Contents (19 chapters)
1
Part 1: Introduction
6
Part 2: App Fundamentals
10
Part 3: Data
14
Part 4: Advanced React

Using React context

In this section, we will learn a feature in React called context. We will then refactor the app from the last section to use React context.

Understanding React context

React context is an object that can be accessed by components. This object can contain state values, so it provides a mechanism for sharing state across components.

A context is created using a createContext function as follows:

const SomeContext = createContext<ContextType>(defaultValue);

A default value for the context must be passed into createContext. It also has a generic type parameter for the type that represents the object created by createContext.

The context also contains a Provider component that needs to be placed above components requiring access to the context object in the component tree. A provider wrapper component can be created that stores the shared state and passes it to the context Provider component as follows:

export function SomeProvider({ children...