constructor(props){super(props);this.state={arr:[]};}componentDidMount(){//使用fetch用于网络加载数据fetch("http://api.shujuzhihui.cn/api/news/list?appKey=3e50f800ce7f4cdd9eda8d1c1ca71792&category;=娱乐").then(response=>response.json()).then(responseJson=>