Book Image

React Key Concepts

By : Maximilian Schwarzmüller
Book Image

React Key Concepts

By: Maximilian Schwarzmüller

Overview of this book

As the most popular JavaScript library for building modern, interactive user interfaces, React is an in-demand framework that’ll bring real value to your career or next project. But like any technology, learning React can be tricky, and finding the right teacher can make things a whole lot easier. Maximilian Schwarzmüller is a bestselling instructor who has helped over two million students worldwide learn how to code, and his latest React video course (React — The Complete Guide) has over six hundred thousand students on Udemy. Max has written this quick-start reference to help you get to grips with the world of React programming. Simple explanations, relevant examples, and a clear, concise approach make this fast-paced guide the ideal resource for busy developers. This book distills the core concepts of React and draws together its key features with neat summaries, thus perfectly complementing other in-depth teaching resources. So, whether you've just finished Max’s React video course and are looking for a handy reference tool, or you've been using a variety of other learning materials and now need a single study guide to bring everything together, this is the ideal companion to support you through your next React projects. Plus, it's fully up to date for React 18, so you can be sure you’re ready to go with the latest version.
Table of Contents (16 chapters)

Summary and Key Takeaways

  • React components are re-evaluated (executed) whenever their state changes or the parent component is evaluated.
  • React optimizes component evaluation by calculating required user interface changes with help of a virtual DOM first.
  • Multiple state updates that occur at the same time and in the same place are batched together by React. This ensures that unnecessary component evaluations are avoided.
  • The memo() function can be used to control component function executions.
  • memo() looks for prop value differences (old props versus new props) to determine whether a component function must be executed again.
  • useMemo() can be used to wrap performance-intensive computations and only perform them if key dependencies changed.
  • Both memo() and useMemo() should be used carefully since they also come at a cost (the comparisons performed).
  • The initial code download size can be reduced with help of code splitting via the lazy() function (in...