what is react pure component code example

Example 1: react with pure components

Simple example of react pure component

import React from 'react';

class PercentageStat extends React.PureComponent {

  render() {
    const { label, score = 0, total = Math.max(1, score) } = this.props;

    return (
      <div>
        <h6>{ label }</h6>
        <span>{ Math.round(score / total * 100) }%</span>
      </div>
    )
  }
}

Example 2: pure components

import { withRouter } from 'react-router-dom';

class MyComponent extends React.Component {
  render () {
    this.props.history;
  }
}

withRouter(MyComponent);

Example 3: pure components

import React from 'react';
import { withRouter } from 'react-router';

// variable which will point to react-router history
let globalHistory = null;

// component which we will mount on top of the app
class Spy extends React.Component {
  constructor(props) {
    super(props)
    globalHistory = props.history; 
  }

  componentDidUpdate() {
    globalHistory = this.props.history;
  }

  render(){
    return null;
  }
}

export const GlobalHistory = withRouter(Spy);

// export react-router history
export default function getHistory() {    
  return globalHistory;
}