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What Is React?

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What Is React?

Thinking about adopting React.js for your next front-end development project? Read on to get a great overview of why it is so popular.

· Web Dev Zone ·
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Deploying code to production can be filled with uncertainty. Reduce the risks, and deploy earlier and more often. Download this free guide to learn more. Brought to you in partnership with Rollbar.

React is an extremely powerful library created by Facebook for front-end development, which allows the developer to build user interfaces.










React is a JavaScript library and an extremely powerful, flexible, high-speed tool for working with dynamic UIs, especially when the UI is related to data state.

At the end of September 2017, Facebook announced the release of React v16.0, which included new features, like error boundaries, portals, improved server-side rendering, and reduced file size, and a complete rewrite of the internals. The rewrite will ultimately enable support for asynchronous rendering, which makes it possible to process large component trees without blocking the main execution thread.

As React is component-based, you can build encapsulated components, where each manages its own state. You can use and reuse these components to create complex UIs.

It can also be used to render on the server using Node.js and build powerful mobile apps with React Native.

React’s usage allows developers to create single-page applications (SPAs), which avoid refreshing to display new content, bringing the user a great look and feel.

Here is a link to an extensive list of sites that are using this library. For a quick glance, here are some of them:

  • Facebook
  • Airbnb
  • Dropbox
  • Instagram
  • Khan Academy
  • Netflix
  • PayPal
  • Reddit
  • Uber

So, a lot of sites and companies use React. Want to know why? Here’s what React has to offer!

Virtual DOM

React works really quickly when used the right way. One of the most important rules is to correctly utilize the features provided by its virtual DOM. The main problem with the DOM is the slow process of creating dynamic user interfaces. But instead of interacting with the DOM directly, you can work with a lightweight copy.

You can make changes to the copy and then apply those changes to the actual DOM. While you’re at it, you can also compare the DOM tree with its virtual copy. If there are differences between the two, only the differences will be redrawn. This avoids costly DOM operations and performs updates in a very efficient manner.

State

The logic is based on state, which can also be thought of as private data. Any changes to the UI should be related to state changes. This approach provides automatic DOM re-rendering, so developers don’t need to worry about UI changes.

By correctly utilizing state, it is easy to create well-flowing, dynamic, secure, and user-friendly applications.

To help with state and data, developers can seamlessly integrate Redux, which is a predictable data-flow architecture. Redux maintains the state of an entire application in a single immutable state tree, which can’t be changed directly.

Lifecycle

React components have their own lifecycles based on state and render logic. Developers can track state changes and component mount events. With all of its lifecycle features, React provides a very powerful and flexible way to work with data and UI.

It is possible to control the moment at which the component is created and inserted into the DOM, with methods like render() and componentDidMount(); check when a component is being re-rendered, with componentWillReceiveProps(); and handle unmounting. It is now also possible to catch errors during rendering with  componentDidCatch(), which allows you to recover gracefully.

Other Great Things

JSX

What is JSX? Simply put, it is an extension for JavaScript that works hand-in-hand with React, supporting HTML tags in your JavaScript code.

Using JSX allows you to have the HTML code written inside of the component in your JavaScript code; there’s no need to use external templating engines. This greatly simplifies the development process and makes it easier to understand and write new components.

A simple example of using JSX

A Simple Example of Using JSX

Third-Part Library

There are a lot of third-party libraries created specifically for React (a simple search of the keyword ‘react’ in npm/yarn returns more than 40,000 results). This allows developers to focus on developing and creating the software itself.

This ecosystem is getting larger every day, with countless developers around the world contributing to it.

The Mern Stack

The MERN (MongoDB, Express, React, Node.js) stack is a collection of JavaScript-based technologies used to develop web applications. Together, these components provide an end-to-end solution for building web applications. You can handle the UI part with React, the server side with Node.js and Express, and include the database with MongoDB.

So why use this approach? For one, all of your written code can be in the same language – JavaScript! This can significantly speed up the development of software and help maintain it.

  • Front-end and backend developers use the same programming language.
  • Less effort in integrating the front- and backend together.
  • More reusable code.
  • Uniform data format – JSON.

Using MERN saves time and effort while developing.

Popularity

There are a couple of things to consider when it comes to React's popularity:

  • JavaScript is becoming more and more popular.
  • One-way data binding facilitates easy-to-manage state.
  • Reusable components.
  • MERN stack.
  • Virtual DOM.
  • React Native.

Of course, React also has its disadvantages – for example, it is not a framework, and it is only the V in MVC (model-view-controller) – but there are still a lot of good reasons to use it.

Deploying code to production can be filled with uncertainty. Reduce the risks, and deploy earlier and more often. Download this free guide to learn more. Brought to you in partnership with Rollbar.

Topics:
javascript ,web dev ,react.js ,mern stack

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