如何 map 数组并保留对象的某些属性？

Question

我正在寻找 map 通过数组并返回一个数组，该数组仅具有原始 object 的某些属性。 例如从这里：

[
   {
    lat: 40.621996,
    lon: -74.028679,
    places: 1,
    time: "2019/11/20 22:26:00"
   },
   {
    lat: 40.621996,
    lon: -74.028679,
    places: 1,
    time: "2019/11/20 22:26:00"},
   {
    lat: 40.621996,
    lon: -74.028679,
    places: 1,
    time: "2019/11/20 22:26:00"}
   ]

产生这个：

[
   {
    lat: 40.621996,
    lon: -74.028679
   },
   {
    lat: 40.621996,
    lon: -74.028679
    },
   {
    lat: 40.621996,
    lon: -74.028679
   }
   ]

不确定映射是否是考虑这个问题的正确方法？

Answer 1

 const list = [ { lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00" }, { lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00"}, { lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00"} ]; const result = list.map( o => { return { lat: o.lat, lon: o.lon} }); // or const result1 = list.map(({lat, lon}) => ({lat, lon})); console.log(result); console.log(result1);

您可以使用map方法

Answer 2

映射将起作用。

 const array = [{ lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00" }, { lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00" }, { lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00" } ] const mappedArray = array.map(item => ({ lat: item.lat, lon: item.lon }));

Answer 3

是的需要

 let arr=[ { lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00" }, { lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00"}, { lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00"} ]; console.log(arr.map(({ lat, lon }) => ({lat, lon})));

Answer 4

 const data = [{ lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00" }, { lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00" }, { lat: 40.621996, lon: -74.028679, places: 1, time: "2019/11/20 22:26:00" } ]; const res = data.map(({lat, lon}) => ({lat, lon})); console.log(res);

Answer 5

你可以用 map 做到这一点

var data = [
            {
              lat: 40.621996,
              lon: -74.028679,
              places: 1,
              time: "2019/11/20 22:26:00"
            },
            {
             lat: 40.621996,
             lon: -74.028679,
             places: 1,
             time: "2019/11/20 22:26:00"},
            {
             lat: 40.621996,
             lon: -74.028679,
             places: 1,
             time: "2019/11/20 22:26:00"}
             ];

var newData = data.map((d)=>{
 ['places', 'time'].forEach(e => delete d[e]);
 return d;
});