ECMAScript2015(ES6) is the latest version of the ECMAScript standard.

React is a declarative, efficient, and flexible JavaScript library for building user interfaces.

In the earlier days of React development, many programms were written in ES5. Howerver, as ES6 is more widely accepted now and with the help of transplier tools like Babel, we can gradually retire some ES5 code and adopt some ES6 new features in React development.

Here is a check list to help you translate your ES5 code to newer version in React.
You are welcome to contribute with more items provided below.

Quick links

1. require => import
1. createClass => extends React.Component
1. module.exports => export default
1. name: function() => name()
1. getDefaultProps and propTypes
1. getInitialState
1. Destructuring & spread attributes

$3

ES5

``js
//ES5
var React = require("react");
var PropTypes = React.PropTypes;
`

ES6

`js
import React, { Component, PropTypes } from 'react';
`

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$3

ES5

`js
var Mycomponent = React.createClass({
render: function() {
return (



);
},
});
`

ES6

`js
class Mycomponent extends React.Component {
render() {
return (



);
}
}
`
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$3

ES5

`js
var Mycomponent = React.createClass({
render: function() {
return (


);
},
});

module.exports = Mycomponent;

`

ES6

`js
export default class Mycomponent extends React.Component {
render() {
return (



);
}
}
`
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$3

ES5

`js
var Mycomponent = React.createClass({
componentWillMount: function(){

},
render: function() {
return (


);
},
});

module.exports = Mycomponent;

`

ES6

`js
export default class Mycomponent extends React.Component {
componentWillMount() {

}
render() {
return (



);
}
}
`

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$3

ES5

`js
var Video = React.createClass({
getDefaultProps: function() {
return {
autoPlay: false,
maxLoops: 10,
};
},
propTypes: {
autoPlay: React.PropTypes.bool.isRequired,
maxLoops: React.PropTypes.number.isRequired,
posterFrameSrc: React.PropTypes.string.isRequired,
videoSrc: React.PropTypes.string.isRequired,
},
render: function() {
return (

);
},
});
`

ES6

`js
class Video extends React.Component {
render() {
return (

);
}
}
Video.defaultProps = {
autoPlay: false,
maxLoops: 10,
};
Video.propTypes = {
autoPlay: React.PropTypes.bool.isRequired,
maxLoops: React.PropTypes.number.isRequired,
posterFrameSrc: React.PropTypes.string.isRequired,
videoSrc: React.PropTypes.string.isRequired,
};
`

ES7:

`js
class Video extends React.Component {
static defaultProps = {
autoPlay: false,
maxLoops: 10,
}
static propTypes = {
autoPlay: React.PropTypes.bool.isRequired,
maxLoops: React.PropTypes.number.isRequired,
posterFrameSrc: React.PropTypes.string.isRequired,
videoSrc: React.PropTypes.string.isRequired,
}
state = {
loopsRemaining: this.props.maxLoops,
}
}
`

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$3

ES5

`js
var Header = React.createClass({
getInitialState: function() {
return {
title: this.props.title
};
},
});
`

ES6

`js
export default class Header extends Component {
constructor(props) {
super(props);
this.state = {
title: props.title
};
}
}
`

ES7

`js
export default class Header extends Component {
state = {
title: this.props.title
};

// followed by constructor...
}
`

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$3

`js
class AutoloadingPostsGrid extends React.Component {
render() {
var {
className,
...others, // contains all properties of this.props except for className
} = this.props;
return (


);
}
}

``

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Reference

* React
* Babel
* ECMAScript 6 support in Mozilla
* React on ES6+
* Converting React project from ES5 to ES6
* React/React Native 的ES5 ES6写法对照表

Roadmap

- [ ] Include all ES5 to ES6+ instructions for React
- [ ] We may Implement ESlint plugin like ESlint-Plugin-React-5-to-6
- [ ] We may Include instructions for configuring Babel with different stages

License

MIT