1.遍历选项,option里的value去掉,把value写到select里
2.onChange方法写到select标签里
import React, { Component } from 'react' class App extends Component { constructor(props) { super(props); this.state = { cities:["北京","上海","广州"], //选项 city:"广州" // 默认选项 } } render() { return ( <div> {/* value放在select里 select框也要onChcange*/} <select value={this.state.city} onChange={(e)=>this.getValue(e)}> { // 遍历option this.state.cities.map((ele,index)=>{ return( <option key={index}>{ele}</option> ) }) } </select> </div> ); } getValue=(event)=>{ //获取被选中的值 console.log(event.target.value); this.setState({ //默认值改变 city:event.target.value }) } } export default App;