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                <div id='root'>




const domContainer = document.querySelector('#root')

// 绑定在外层的原生点击事件 非documemt层
domContainer.addEventListener('click', e => {
  console.log('root click event',e)
  console.log('root click')

class InnerDom extends React.Component {
  componentDidMount () {
     document.addEventListener('click', () => {
      console.log('document click')

  outClick = (e) => {
    console.log('out dom click')

  innerClick = (e) => {
    console.log('inner click nativeEvent',e.nativeEvent)
    console.log('inner dom click')
  // refCb = (dom) => {
  //     //这里我就没有去解绑了
  //     dom && dom.addEventListener('click',this.innerClick)
  // }

  render () {
    return <div onClick={this.outClick}>
      <button onClick={this.innerClick} > 测试冒泡</button>

ReactDOM.render(<InnerDom />, domContainer)