Simpest React Component

simplestReactComponent.js

//引入 React 及 Component 
import React, {Component} from 'react'

//建立一個名為 App 的類別並繼承 Component
class App extends Component{    
    render(){
        return (
        <div>Hello React</div>
        )
    }
}

//匯出寫好的 App
export default App