// 阅读图书 readBook:function(e){ var that = this // 获取当前点击图书的ID let id = e.currentTarget.dataset.id // 获取当前点击图书的Url let fileUrl = e.currentTarget.dataset.file // 查看本地缓存 let path =wx.getStorageSync(id) // 未曾下载过 if(path ==''){ // 切换到下载时的蒙层 that.setData({ isDownloading:true }) // 先下载图书 const downloadTask = wx.downloadFile({ url:fileUrl, success:function(res){ // 关闭下载时的蒙层 that.setData({ isDownloading:false }) // 下载成功 if (res.statusCode == 200){ // 获取地址 path = res.tempFilePath // 保存并打开图书 that.saveBook(id,path) } // 连上服务器，下载失败 else{ that.showTips('暂时无法下载') } }, //请求失败 fail:function(e){ // 关闭下载时的蒙层 that.setData({ isDownloading:false }) that.showTips('无法连接到服务器!') } }) // 监听当前文件下载的下载速度 downloadTask.onProgressUpdate((res) =>{ let progress = res.progress that.setData({ percentNum: progress }) }) } else{ // 打开图书 that.openBook(path) } }, 当我点击图书下载前，无错误，但当我点击时，只会提示弹出‘无法连接到服务器’这个消息框，但是无法下载，并出错以下错误 thirdScriptError Cannot read property 'onProgressUpdate' of undefined; [Component] Event Handler Error @ pages/index/index#bound readBook TypeError: Cannot read property 'onProgressUpdate' of undefined     at me.readBook (http://127.0.0.1:52924/appservice/pages/index/index.js:141:18)     at Object.r.safeCallback (http://127.0.0.1:52924/appservice/__dev__/WAService.js:2:1434440)     at http://127.0.0.1:52924/appservice/__dev__/WAService.js:2:1552253     at s (http://127.0.0.1:52924/appservice/__dev__/WAService.js:2:1561021)     at http://127.0.0.1:52924/appservice/__dev__/WAService.js:2:1552178     at r (http://127.0.0.1:52924/appservice/__dev__/WAService.js:2:1505702) 当我点击图书时，只提示‘无法连接到服务器’这个选项，但是无法下载， ’‘

function getRandomColor(){ let rgb = [] for(let i=0;i<3;i++){ let color = Math.floor(Math.random()*256).toString(16) color = color.length==1?'0'+color:color rgb.push(color) } return '#'+rgb.join('') } //以下为错误提示 VM4193:1 file: pages/index/index.js  unknown: function is a reserved word (118:2)    116 |   },   117 |  > 118 |   function getRandomColor(){       |  ^   119 |     let rgb = []   120 |   for(let i = 0;i<3; i++){   121 |   let color = Math.floor(Math.random() * 256).toString(16) 改成以下方式可以表达，但是反馈的颜色一直是白色，无法随机 //生成随机颜色 getRandomColor: function (){ let rgb = [ ] for ( let i = 0; i< 3; ++i ) { let color = Math.floor(Math.random() * 256).toString(16) color = color.length == 1 ? '0' + color:color rgb.push(color) } return '#' + rgb.join(' ') }

getWeather: function(){ var that = this; wx.request({ url: 'https://free-api.heweather.com/s6/weather/now', data:{ location:that.data.region[1], key:'07e21eda4e604f8dbce0d1' }, success: function(res){ that.setDate({ now:res.data.HeWeather6[0].now }); } })