设置缓存，将JSON数据写进缓存要先转化为string类型 ``` localStorage.setItem('bannerList', JSON.stringify(tempList)); ``` 读取缓存，将缓存中的string类型读取出来后可以转化为JSON类型 ``` var bannerList = JSON.parse(localStorage.getItem('bannerList')) ``` ``` var bannerList = JSON.parse(localStorage.getItem('bannerList')) if(bannerList) { //如果缓存存在，则直接获取数据 this.bannerList = bannerList; }else { //不存在则发送ajax请求 moviemodel.getInTheaters().then(res=>{ let tempList = []; res.body.subjects.slice(0, 3).forEach(ele => { tempList.push(ele.images.small) }); this.bannerList = tempList; //将bannerList转化为字符串类型存入缓存 localStorage.setItem('bannerList', JSON.stringify(tempList)); }) } ```