const chart = new F2.Chart(config);
   chart.legend(false);
   chart.point()
     .position('date*weight')
     .size('tag', function (val) {
       return val ? 3 : 0;
     })
     .style('tag', {
       fill: function fill(val) {
         return '#0ac7d9'
       },
       stroke: '#fff',
       lineWidth: 1
     });
   chart.source(chartData, {
     date: {
       range: [0, 1],
       type: 'timeCat',
       mask: 'MM-DD'
     },
     weight: {
       max: 120,
       tickCount: 5,
       alias: '体重(kg)'
     }
   });
   chart.tooltip({
     showCrosshairs: true,
     showTitle: false,
     showItemMarker: false,
     snap: true,
     crosshairsType: 'xy',
     onShow: function onShow(ev) {
       return (ev.items = ev.items.splice(1));
     },
   });
   chart.area().position('date*weight').color('#0ac7d9').shape('smooth').adjust('stack');
   chart.line().position('date*weight').color('#0ac7d9').shape('smooth').adjust('stack');
   chart.render();
   f2Chart = chart;
   return chart;

<view class="bmi-item" wx:for="{{bmiArray}}" wx:for-item="item" wx:for-index="index" wx:key="index">
    <view class="bmi-start" wx:if="{{item.start !== ''}}">{{item.start}}</view>
    <view class="bmi-middle">{{item.desc}}</view>
    <view class="bmi-end" wx:if="{{item.end !== ''}}">{{item.end}}</view>
</view>

[{
   start:0,
   desc:'偏瘦',
   end:''
 },{
   start: 18.5,
   desc: '正常',
   end:''
 },{
   start: 24,
   desc: '偏胖',
   end: ''
 },{
   start:27,
   desc:'肥胖',
   end:40,
 }
 ]

  // 云函数入口文件
const cloud = require('wx-server-sdk')
const rq = require('request-promise');

cloud.init()

// 云函数入口函数
exports.main = async (event, context) => {
  const wxContext = cloud.getWXContext()
  const url = `xxxx`
  const res = await rq(url);
  return res;
}

if (!params){
    console.error(`[数据库]${dbName} [新增记录],参数空`);
}
const data = {
    data: params  //切记，这里params，需要时{},形式
}
const db = wx.cloud.database();
return db.collection(dbName).add(data).then((res) => {
    console.log(`[数据库]${dbName} [新增记录] 成功，记录 _id:`, params, res._id)
}).catch(err => {
    console.error(`[数据库]${dbName} [新增记录] 失败：`, params, err)
})