mpvue下拉分页加载

//html
<div  v-for="item in datas" :key="item" >{{item}}</div>
//js
data:{
 p:1,
datas:[]
} ,
methods:{
 echartdatas() {
    wx.request({
          url: that.url,
          method: "POST",
          header: {
            "content-type": "application/json"
          },
          data: {
            pageNum:that.p//页数  数量后端有返
          },
          success: function(res) {
            that.datas = [...that.datas, ...res.data.data]
           
          }
        })
     }
  },
onReachBottom:function(){
      this.p1++
      this.echartdatas();
  }