Node JS Nested Array Transformation

Question

I am trying to transform following array but it's only transforming single level. multiple remain same want to remove entity for each level of object.

I have used the map to modify object not sure if there are others method for the multi level

Here is the array


const source = [
  {
    "block_id": 1,
    "entity": 100,
    "block_name": "test 1",
    "children": [
      {
        "block_id": 2,
        "entity": 101,
        "block_name": "test 2",
        "children": [
          {
            "block_id": 3,
             "entity": 105,
            "block_name": "test 2",
          }

        ]
      }
      
    ],
  }
]

Tried following code to transform

function trans(item) {
  const items = Array.isArray(item) ? item : [item];
    return items.map( t => {
        return { block_id: t.block_id, block_name: t.block_name, children: t.children };
    });
}

I am getting following

Output

[
  {
    "block_id": 1,
    "block_name": "test 1",
    "children": [
      {
        "block_id": 2,
        "entity": 101,
        "block_name": "test 2",
        "children": [
          {
            "block_id": 3,
            "entity": 105,
            "block_name": "test 2",
          }

        ]
      }
      
    ],
  }
]

Expected

[
  {
    "block_id": 1,
    "block_name": "test 1",
    "children": [
      {
        "block_id": 2,
        "block_name": "test 2",
        "children": [
          {
            "block_id": 3,
            "block_name": "test 2",
          }

        ]
      }
      
    ],
  }
]

Please help

You can do it well using recurison.

Aalexander
– Aalexander

2021-02-18 09:52:11 +00:00
Commented Feb 18, 2021 at 9:52 — Aalexander
– Aalexander, Commented Feb 18, 2021 at 9:52

Rajneesh · Accepted Answer · 2021-02-18 09:56:57Z

2

Wanted result can be implemented easily with recursion:

const source = [ { "block_id": 1, "entity": 100, "block_name": "test 1", "children": [ { "block_id": 2, "entity": 101, "block_name": "test 2", "children": [ { "block_id": 3, "entity": 105, "block_name": "test 2", } ] } ], }];

const transform=arr=>arr.map(({entity,...rest})=> rest.children ? ({...rest, children: transform(rest.children)}) : rest);

console.log(transform(source));

answered Feb 18, 2021 at 9:56

Rajneesh

5,3181 gold badge10 silver badges20 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

screw spike · Accepted Answer · 2021-02-18 10:17:24Z

if you don't mind to change your origin Array ,you can try this codes:

function trans(item, element) {
    const items = Array.isArray(item) ? item : [item];
    items.forEach(t => {
        if (typeof t === 'object') {
            if (element in t) {
                delete t[element]
            }
            for (const argument in t) {
                const item = t[argument]
                if (typeof item === 'object') {
                    trans(item,element)
                }
            }
        }
    });
}

and the result is:

const source = [
    {
        "block_id": 1,
        "entity": 100,
        "block_name": "test 1",
        "children": [
            {
                "block_id": 2,
                "entity": 101,
                "block_name": "test 2",
                "children": [
                    {
                        "block_id": 3,
                        "entity": 105,
                        "block_name": "test 2",
                    }

                ]
            }

        ],
    }
]

function trans(item, element) {
    const items = Array.isArray(item) ? item : [item];
    items.forEach(t => {
        if (typeof t === 'object') {
            if (element in t) {
                delete t[element]
            }
            for (const argument in t) {
                const item = t[argument]
                if (typeof item === 'object') {
                    trans(item, element)
                }
            }
        }
    });
}

trans(source, 'entity')

console.log(JSON.stringify(source, null, 2));

Collectives™ on Stack Overflow

Node JS Nested Array Transformation

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related