Extract data from object based on key in JavaScript

Question

I am trying to find the property value of an object based on key. I have below function getData which returns the data based on key passed as input parameter.

const getData = (key) => {
  let row = {isSelected: true, Data: {Id: '1A', Value: 'LD'}};
  return row[key];
}
console.log(getData('Data'));

In normal scenario it is working fine but how can I get the property value from nested object Data.Value.

If I call getData function as getData('Data.Value'), It should return LD.

Does this answer your question? [Accessing nested JavaScript objects and arrays by string path](https://stackoverflow.com/questions/6491463/accessing-nested-javascript-objects-and-arrays-by-string-path) — pilchard, Apr 13 '22 at 10:02
@pilchard, I had a look on the answer but don't find the solution for my problem. — Ayaz, Apr 13 '22 at 10:10
Every answer is a solution to your problem, you need to parse the string and then iteratively or recursively access the object. Another duplicate would be [Javascript: Get deep value from object by passing path to it as string](https://stackoverflow.com/questions/8817394/javascript-get-deep-value-from-object-by-passing-path-to-it-as-string) — pilchard, Apr 13 '22 at 10:13
@pilchard, my bad. there were too many tabs open and I looked at wrong tab. It has the answer on url suggested by you. However I would prefer short and simple solution by Ori. — Ayaz, Apr 13 '22 at 10:40
The lodash solution is also included in the duplicates https://stackoverflow.com/a/31303609/13762301 — pilchard, Apr 13 '22 at 10:41

score 1 · Accepted Answer · answered Apr 13 '22 at 10:26

You can use lodash's _.get() function that returns the value at a path:

const getData = path => {
  const row = {isSelected: true, Data: {Id: '1A', Value: 'LD', InnerData: {Id: 1, Value: "Something"}}};
    
  return _.get(row, path);
}

console.log(getData('Data'));
console.log(getData('Data.Value'));
console.log(getData('Data.InnerData.Value'));

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.21/lodash.min.js" integrity="sha512-WFN04846sdKMIP5LKNphMaWzU7YpMyCU245etK3g/2ARYbPK9Ub18eG+ljU96qKRCWh+quCY7yefSmlkQw1ANQ==" crossorigin="anonymous" referrerpolicy="no-referrer"></script>

Second answer in the linked duplicate https://stackoverflow.com/a/31303609/13762301 — pilchard, Apr 13 '22 at 10:43

score 0 · Answer 2 · answered Apr 13 '22 at 10:11

0

I would suggest accessing the nested value like this:

getData("Data").Value

answered Apr 13 '22 at 10:11

elephena

31
3

I can't hardcode the .Value. It may have multilevel nested object and property names are dynamic. – Ayaz Apr 13 '22 at 10:13
You could access it like this too for one level of nesting: `getData("Data")[someVar]` – elephena Apr 13 '22 at 11:29

Nbody · Answer 3 · 2022-04-13T10:24:21.663

0

This is what you want. It is not matter how deep is your row. Try this. It would be multilevel nested object too. For example

Data.InnerData.Value...

const getData = (key) =>{
    let row = {isSelected: true, Data: {Id: '1A', Value: 'LD', InnerData: {Id: 1, Value: "Something"}}};
    var keys = key.split('.');
    var res = row;
    for(var i=0; i < keys.length; i++){
        res = res[keys[i]];
    }
    
    return res;
}

console.log(getData('Data.InnerData.Value'));

edited Apr 13 '22 at 10:24

answered Apr 13 '22 at 10:17

Nbody

1,168
7
33

He said that he can't hardcode the key to get the data. – Ritik Banger Apr 13 '22 at 10:18
if it is dynamic send dynamic key to getData(). For example get keys from database and send it to getData() – Nbody Apr 13 '22 at 10:20

score 0 · Answer 4 · answered Apr 13 '22 at 10:30

0

When you have dynamic object keys you can use javascript Object.keys method.

var data = getData("Data")
var dynamicKeys = Object.keys(data)

for(int i=0; i < dynamicKeys.length; i++){
   console.log(data[dynamicKeys[i]])
}

answered Apr 13 '22 at 10:30

Usama

1,038
9
22

score 0 · Answer 5 · answered Apr 13 '22 at 10:31

If you are certain that your object goes two level at most, you can try this simple solution

const isObject = (value) => {
   return typeof value === 'object' && !Array.isArray(value) && value !== null;
};

const testData = { isSelected: true, data: { id: '1A', value: 'LD' } };

const getData = (key) => {
   const keys = key.split('.');
   if (isObject(testData[keys[0]])) {
      return testData[keys[0]][keys[1]];
   }
   return testData[keys[0]];
};

console.log(getData('data.id'));

Extract data from object based on key in JavaScript

5 Answers5