React Refs 简单演示

react 支持一种非常特殊的属性 ref ，可以用来绑定到 render() 输出的任何组件上

import react, { component } from 'react';
import reactdom from 'react-dom';
import './index.css';
import * as serviceworker from './serviceworker';

class focus extends component{
  constructor(props){
    super(props);
    this.focusfn=this.focusfn.bind(this);
  }

  focusfn(){
    this.refs.myinput.focus();
  }

  render(){
    return(
      <div>
        <input type="text" ref="myinput" />
        <br/>
        <button onclick={this.focusfn}>点我</button>
      </div>
    )
  }
}

  reactdom.render(
    <div>
       <focus />
    </div>,
    document.getelementbyid('example')
  );

serviceworker.unregister();