What is React JS?
ReactJS is an open-source, component based front end library responsible only for the view layer of the application. It is maintained by Facebook. ReactJS uses virtual DOM based mechanism to fill in data (views) in HTML DOM. The virtual DOM works fast owning to the fact that it only changes individual DOM elements instead of reloading complete DOM every time.
A React application is made up of multiple components, each responsible for outputting a small, reusable piece of HTML. Components can be nested within other components to allow complex applications to be built out of simple building blocks. A component may also maintain internal state - for example, a TabList component may store a variable corresponding to the currently open tab.
React "reacts" to state changes in your components quickly and automatically to rerender the components in the HTML DOM by utilizing the virtual DOM. The virtual DOM is an in-memory representation of an actual DOM. By doing most of the processing inside the virtual DOM rather than directly in the browser's DOM, React can act quickly and only add, update, and remove components which have changed since the last render cycle occurred.
Virtual DOM - DOM is the process that makes things “change” on screen without a user having to manually refresh a page. If a developer uses JSX to manipulate and update its DOM, React JS creates something called a Virtual DOM. The Virtual DOM (like the name implies) is a copy of the site’s DOM, and React JS uses this copy to see what parts of the actual DOM need to change when an event happens (like a user clicking a button).
It follows component-based approach.
Easy to create smaller components and build large-scale applications.
The main goal is to build large-scale high-performance applications with smaller and reusable stateful components.
The main objective of React Training is to create smaller components to build Interactive User interfaces.
Why Learn ReactJS?
ReactJS presents streamlined solutions to some of front-end programming’s most persistent issues. ReactJS is fast, scalable, flexible, powerful, and has a robust developer community that’s rapidly growing. There’s never been a better time to learn React.
React.js Course Curriculum
Using ReactJS with TypeScript
ReactJS component written in TypeScript
Installation and Setup
Stateless React Components in TypeScript
Stateless and property-less Components
State in React
Props in React
Passing down props using spread operator
Props.children and component composition
Detecting the type of Children components
React Component Lifecycle
Forms and User Input
React AJAX call
Communication Between Components
Stateless Functional Components
Introduction to Server-Side Rendering
Setting Up React Environment
Using React with Flow
Props in JSX
Children in JSX
Keys in react
Higher Order Components
React with Redux
React.js Interview Questions & Answers
What you will learn in ReactJS course?
You’ll develop a strong understanding of React’s most essential concepts: JSX, components, and storing information via props and state. You’ll be able to combine these ideas in React’s modular programming style.
By the end of the ReactJS course, you'll be able to learn:
How the React command-line development tools work
How to build components using both classes and Hooks
How to create views using the JSX syntax.
How to structure code using the Container Presentation pattern
How to add Typescript support to a React project
How to fetch Json data from a remote API
How the component lifecycle works
How to build a project with the React Router
How to isolate application state with Redux
How to write unit tests for your React code