如何动态传递数组值作为对象道具？

Question

I need to treat array values as props of object. For example:

let arr = ['masa_icerik', 'urunler', 0, 'urun_adet'];
let obj = {
  "_id": "5c13bd566704aa5e372dddcf",
  "masa_id": 3,
  "masa_numara": 3,
  "masa_magaza": 1,
  "masa_icon": "kola",
  "masa_adi": "salon 3",
  "masa_durum": 1,
  "masa_icerik": {
    "adisyon": "J1554745811908",
    "urunler": [{
      "urun_adet": 14,
      "urun_fiyat": 3,
      "urun_id": "5c16686b93d7b79ae6367864",
      "urun_odenen": 0
    }, {
      "urun_adet": 1,
      "urun_fiyat": 5,
      "urun_id": "5c16686b93d7b79ae6367865",
      "urun_odenen": 0
    }]
  },
  "masa_acilis": "2019-04-08T17:50:12.052Z",
  "masa_acan": "5c1eda01d1f4773110dd6ada"
};

I have an array and an object like above and I want to do something like this:

let res;
arr.forEach(elem => {
   res = obj[elem];
});

and after that I need to get something like :

obj['masa_icerik']['urunler'][0]['urun_adet']

The number of the values is dynamic from server. Thats why i need something like this. Is there any way to do that? I need to change that property and return the changed obj.

Answer 1

You can use forEach loop to loop thru the array and store it to a temp variable. If all elements exist, it will change the value.

 let arr = ['a', 'b', 'c']; let obj = {'a':{'b':{'c':1}}}; let newValue = "NEW VALUE"; let temp = obj; arr.forEach((o, i) => { if (i < arr.length - 1) temp = temp[o] || null; else if (temp !== null && typeof temp === "object" ) temp[o] = newValue; }); console.log(obj);

---

If there are multiple multiple object properties missing in the last part of the array.

 let arr = ['a', 'b', 'c', 'd']; let obj = {'a': {'b': {}}}; let newValue = "NEW VALUE"; let temp = obj; arr.forEach((o, i) => { if (i < arr.length - 1) { if (!temp[o]) temp[o] = {[arr[i + 1]]: {}}; temp = temp[o]; } else if (temp !== null && typeof temp === "object") temp[o] = newValue; }); console.log(obj);

Answer 2

You can use references

Here idea is

• Initialize val with object reference
• Loop through array and keep setting new reference to val

 let arr = ['a','b','c']; let obj = {'a':{'b':{'c':1}}}; let getMeValue = (arr) => { let val=obj; arr.forEach(e => val = val && val[e] ) return val } console.log(getMeValue(arr)) console.log(getMeValue([1,2,3]))

UPDATE: I want to change values

 let arr = ['a','b','c']; let obj = {'a':{'b':{'c':1}}}; let getMeValue = (arr) => { let val = obj arr.forEach((e,i) => { if(i === arr.length-1 && val){ val[e] = 5 } else { val = val && val[e] } }) return obj } console.log(getMeValue(arr))

Answer 3

I am not fully understanding where you are getting the new values from but I think this will get you on the right track.

let newObj = {};

arr.map(each => {
   newObj[each] = "new value";
 })

console.log(newObj);

Answer 4

I'm not sure about your requirment here, I guess you want the below:

 let func = (arr, value)=>{ r = {}; r[arr[arr.length-1]] = value; for(let i = arr.length-2; i>=0; i--){ obj = {}; obj[arr[i]] = r; r = obj; } return r; } console.log(func(['a', 'b', 'c'], 1));