map遍历数组返回包含所需字段的对象

假如dataList为后台假数据，我想分别得到number和chargeTime、number和freeTime，来分别画图，就可以这么写，当然直接for循环更可以。

const dataList = {
    list:[
        {
            number: "0",
            chargeTime: 2,
            freeTime: 5
        },{
            Number: "1",
            chargeTime: 8,
            freeTime: 9
        },
        ......
      ]};        

 const chargeTimeAndNumber = dataList.list.map(item => ({
    number:item.number,
    chargeTime:item.chargeTime
}));
 const freeTimeAndNumber = dataList.list.map(item => ({
    number:item.number,
    freeTime:item.freeTime
}));