How can I filter nested object in a complex array in React Native

After handle the response data I got an array like below in React-Native

[{
  "children": [],
  "data": {
    "catCd": "C000000146",
    "catGrpCd": "CG00000135",
    "catNames": [Array],
    "catNm": "Game Design",
    "parentCatCd": "C000000143",
    "parentCatCdPath": "C000000143.C000000146",
    "usedFlag": true
  },
  "hasChildren": false,
  "id": "C000000146",
  "key": "C000000146",
  "sortOrder": 3
}, {
  "children": ["C000000144", "C000000145", "C000000146"],
  "data": {
    "catCd": "C000000143",
    "catGrpCd": "CG00000135",
    "catNames": [Array],
    "catNm": "Design",
    "parentCatCd": null,
    "parentCatCdPath": "C000000143",
    "usedFlag": true
  },
  "hasChildren": true,
  "id": "C000000143",
  "key": "C000000143",
  "sortOrder": 1
}, {
  "children": ["C000000166"],
  "data": {
    "catCd": "C000000144",
    "catGrpCd": "CG00000135",
    "catNames": [Array],
    "catNm": "3D & Animation",
    "parentCatCd": "C000000143",
    "parentCatCdPath": "C000000143.C000000144",
    "usedFlag": true
  },
  "hasChildren": true,
  "id": "C000000144",
  "key": "C000000144",
  "sortOrder": 1
}, {
  "children": [],
  "data": {
    "catCd": "C000000166",
    "catGrpCd": "CG00000135",
    "catNames": [Array],
    "catNm": "Depth1",
    "parentCatCd": "C000000144",
    "parentCatCdPath": "C000000143.C000000144.C000000166",
    "usedFlag": true
  },
  "hasChildren": false,
  "id": "C000000166",
  "key": "C000000166",
  "sortOrder": 1
}, {
  "children": [],
  "data": {
    "catCd": "C000000145",
    "catGrpCd": "CG00000135",
    "catNames": [Array],
    "catNm": "Design Tools",
    "parentCatCd": "C000000143",
    "parentCatCdPath": "C000000143.C000000145",
    "usedFlag": true
  },
  "hasChildren": false,
  "id": "C000000145",
  "key": "C000000145",
  "sortOrder": 2
}, {
  "children": [],
  "data": {
    "catCd": "C000000167",
    "catGrpCd": "CG00000135",
    "catNames": [Array],
    "catNm": "Design 01",
    "parentCatCd": null,
    "parentCatCdPath": "C000000167",
    "usedFlag": true
  },
  "hasChildren": false,
  "id": "C000000167",
  "key": "C000000167",
  "sortOrder": 1
}, {
  "children": ["C000000143", "C000000167"],
  "data": null,
  "hasChildren": true,
  "id": "C000000095",
  "key": "C000000095",
  "sortOrder": 0
}]

Finally I want to filter and get all the element that has parentCatCD : null. Because I am new to react and have tried a lots but nothing works. (map, filter, some, etc …), I always got undefined is not an object error when I try to filter them.

Could you please show me the way to solve this problem, thanks in advanced.

So my code :

  function filterData(arr: any) {
    let newArray = arr.filter(function(item:any){
      return item.data['parentCatCd'] == null;
   }).map(function({data} : {data:any}){
       return {data};
   });
  }

error : null is not an object (evaluating ‘item.data[‘parentCatCd’])

>Solution :

Ok, so you can try this.

let filteredData = response.filter(e => e.data && e.data.parentCatCd === null);

This will return you that data where the parentCatCd is null.