how to flattern the array of object in javascript

I am trying flattern the array of object . I am able to do that . I just want to know is it correct way to do that or is there any better library available ?

Data

const data = {
      details: [
        {
          item_details: {
            number: "sdas",
            date: "28/07/2022"
          }
        },
        {
          item_details: {
            number: "hello",
            date: "28/07/2022"
          }
        }
      ]
    };

Code

function convetObj(data) {
  let res = {};
  for (let i = 0; i < data.details.length; i++) {
    res[`details[${i}].item_details.number`] =
      data.details[i].item_details.number;
    res[`details[${i}].item_details.date`] = data.details[i].item_details.date;
  }
  return res;
}

console.log(convetObj(data));

Here is my code at CodeSandbox

I am getting same as expected output, but wanted to know is it better way ? any better library available

expected output

{
  details[0].item_details.number:"sdas",
  details[0].item_details.date:"28/07/2022"
  details[1].item_details.number:"hello",
  details[1].item_details.date:"28/07/2022"
}

actual output

{
 "details[0].item_details.number": "sdas",
 "details[0].item_details.date": "28/07/2022",
 "details[1].item_details.number": "hello",
 "details[1].item_details.date": "28/07/2022"
} 

>Solution :

With recursion you can flatten an object of any structure, so it’s generic, can be reused on any object, seems better than flatten object every time manually:

const flatten = (obj, target = {}, path = '') => {
  if(Array.isArray(obj)){
    for(let i = 0; i< obj.length; i++){
      flatten(obj[i], target, `${path}[${i}]`);
    }
  }else if(obj.__proto__ === Object.prototype){
    for(const key in obj){
      flatten(obj[key], target, `${path}${path ? '.' : ''}${key}`);
    }
  }else{
     target[path] = obj;
  }
  
  return target;
};

console.log(flatten(data));

<script>
const data = {
      details: [
        {
          item_details: {
            number: "sdas",
            date: "28/07/2022"
          }
        },
        {
          item_details: {
            number: "hello",
            date: "28/07/2022"
          }
        }
      ]
    };

</script>