//9. 列表渲染class List extends React.Component{state = {list:[1,2,3,4,5],list2:[{id:1,text:'java'},{id:2,text:'js'},{id:3,text:'php'},{id:4,text:'python'},{id:5,text:'node'}]}render(){const arr = this.state.list;const arr2 = this.state.list2;const listItem = []const listItem2 = []//map方式遍历arr.map((item)=>{let li = <li>{item}</li>;listItem.push(li);})//或for循环// for (let i = 0; i < arr.length; i++) {//     let li = <li>{arr[i]}</li>;//     listItem.push(li);// }for (let i = 0; i < arr2.length; i++) {let li = <li key={arr2[i].id}>{arr2[i].text}</li>;listItem2.push(li);}return <div><ul>{listItem}{listItem2}</ul></div>}}ReactDOM.render(<List />,document.getElementById('app'));
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