Namaste React

• React was created by Jordan Walke

parcel

• Dev Build
• Local Server
• HMR = Hot Module Replacement
• File Watching Algoirthim - C++
• Caching - Faster builds
• Image Optimization
• Minification
• Bundling
• HTTPS
• Compress
• Diagnostics
• Error handeling
• Multi core
• Tree shaking
• Consistet Hashig

CORSS issue

https://cors-anywhere.herokuapp.com

Lifecycle hooks

• constructor
• render
• componentWillMount
• componentDidMount
• componentShouldUpdate
• componentDidUpdate
• commmponentwillUnmount

Questions

• Statefull and Stateless components?

• Diffrence between controlled and uncontrolled components?

• What are diffrent lifecycle hooks?

• Explain working of Redux.

• What are the major features of React?

  • Uses JSX syntax, a syntax extension of JS that allows developers to write HTML in their JS code.
  • It uses Virtual DOM instead of Real DOM considering that Real DOM manipulations are expensive.
  • Supports server-side rendering which is useful for Search Engine Optimizations(SEO).
  • Follows Unidirectional or one-way data flow or data binding.
  • Uses reusable/composable UI components to develop the view.

• What is JSX

  • Its a Syntactic Sugar.

• What is the difference between Element and Component? Element is an object AND component is an function

• Diffrence between usememo and React .memo

  • React.memo() is a higher-order component

• What are synthetic events in React?

• What is the difference between Shadow DOM and Virtual DOM?

• What is the difference between createElement and cloneElement?

• Does the lazy function support named exports? No

• Why React uses className over class attribute? because 'class' is already a keyword in javascript.

• What are Fragments? <> </>

• What are portals in React? Portal is a recommended way to render children into a DOM node that exists outside the DOM hierarchy of the parent component.

  ReactDOM.createPortal(child, container);
  

• What is the use of react-dom package?

• What is ReactDOMServer? to use react components on server

  renderToString
  renderToStaticMarkup
  

• How to enable production mode in React?

• React Mixin & React hook.

• Are custom DOM attributes supported in React v16?

• How to add Google Analytics for React Router?

• Is it possible to use async/await in plain React?

• Why are 2 react script files imported ?

• why do we write crossorigin in script tag ? to tell browser that we need to send credentials or nor ( ananomous , use-credentials ) are the two possible values.

TODO

• Error Boundries