for循环中执行promise

let promiseList = [];   //promise返回值的数组
      for (let obj of list) {
        let p = new Promise((resolve, reject) => {
          _this.loadLayer.text = '正在生成【' + obj.label + '】数据文件'
          exportList(obj.url,obj.params)
            .then((response) => {
              response.bussinessName = obj.label;
              resolve(response)
            }).catch((e) => {
              reject(e)
           })
        })
        promiseList.push(p);
      }

_this.loadLayer.loading = true;
      Promise.all(promiseList).then((res) => {
        _this.loadLayer.loading = false;
        console.log(res)
      }).catch((err) => {
        console.log(err)
        _this.loadLayer.loading = false;
      })