react context example es6 classes

import React, { PropTypes, Component } from 'react'
 
class ContextExample extends Component {

 static childContextTypes = {
   config: PropTypes.object,
 }

 getChildContext() {
   return {
     config: this.props.config,
   }
 }

 render() {
   return <div>{this.props.children}</div>
 }
}

class UseContext extends Component {
  static contextTypes = {
    config: PropTypes.object
  }

  render() {
    return <div>{this.context.config.value}</div>
  }

}

it is legacy API example
https://reactjs.org/docs/legacy-context.html