Delete property and its values in all the object

Question

I'm a beginner in javaScript, I have this object MyGraph:

const MyGraph = {
    a: { b: 5, c: 2 },
    b: { a: 5, c: 7, d: 8 },
    c: { a: 2, b: 7, d: 4, e: 8 },
};

I want to delete property "a" and its values in other properties as well to get this result:

const MyGraph = {
    b: { c: 7, d: 8 },
    c: { b: 7, d: 4, e: 8 },
};

I tried like this:

for(let XXX of Object.keys(MyGraph)){
    console.log(XXX.a);
    delete XXX.a;
}

the result of execution:

undefined
undefined
undefined

any help!

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking. — Community, Apr 23 '22 at 11:38
Does this answer your question? [How do I remove a key from a JavaScript object?](https://stackoverflow.com/questions/3455405/how-do-i-remove-a-key-from-a-javascript-object) — Ahmet Firat Keler, Apr 23 '22 at 11:39
duplicate: [Javascript delete nested object properties by name](https://stackoverflow.com/questions/62895132/javascript-delete-nested-object-properties-by-name) — pilchard, Apr 23 '22 at 11:56

Peterrabbit · Accepted Answer · 2022-04-23T11:53:19.430

5

You could use a recursive algorithm :

function del_entries(key, obj) {
  if (obj.hasOwnProperty(key)) {
    delete obj[key];
  }

  // Or with Object.hasOwn, not fully supported by old browsers but more up to date
 /*
 if (Object.hasOwn(obj, key)) {
     delete obj[key]
 }
 */
  
  Object.values(obj).forEach(o=> del_entries(key, o))
}


const MyGraph = {
    a: { b: 5, c: 2 },
    b: { a: 5, c: 7, d: 8 },
    c: { a: 2, b: 7, d: 4, e: 8 },
};

del_entries("a", MyGraph);

console.log(MyGraph)

edited Apr 23 '22 at 11:53

answered Apr 23 '22 at 11:43

Peterrabbit

2,166
1
3
19

you can now recommend the new [`hasOwn()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwn) which takes care of the [issues](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwn#problematic_cases_for_hasownproperty) with `hasOwnProperty` – pilchard Apr 23 '22 at 11:45

ysfiqbl · Answer 2 · 2022-04-23T19:23:55.410

In your code XXX is the key. You need to do graph[XXX] to access the actual object. So instead of XXX.a you should do graph[XXX].a. But this only accounts for objects in graph that have an the key a. You also need to account for key a in graph. Please see the code below. Its a rudimentary example.

If you have one level of nesting then you can use then you can use the code below.

const mygraph = {
  a: { b: 5, c: 2 },
  b: { a: 5, c: 7, d: 8 },
  c: { a: 2, b: 7, d: 4, e: 8 },
};

console.log(mygraph);

function deletePropAndValuesOf(key, graph) {

  for (const k of Object.keys(graph)) {
    if (k === key) {
      delete graph[key];
    } else {
      if (key in graph[k]) {
        delete graph[k][key]
      }
    }
  }
}

deletePropAndValuesOf("a", graph);

console.log(mygraph);

You can copy the code to a .js file and run it using node. e.g.

score -1 · Answer 3 · answered Apr 23 '22 at 12:09

-1

Ive used object destructuring to remove the first array with an a, but could not figure out how to do all the a's's but the code below might help?

const MyGraph = {
a: { b: 5, c: 2 },
b: { a: 5, c: 7, d: 8 },
c: { a: 2, b: 7, d: 4, e: 8 }};
const {a, ...newMyGraph} = MyGraph;
// output
console.log(newMyGraph)

returns

b: {
   a: 5,
   c: 7,
   d: 8
},
c: {
   a: 2,
   b: 7,
   d: 4,
   e: 8
}
}

answered Apr 23 '22 at 12:09

Ahmed Warsama

1

I didn't downvote, and the thought to use destructuring is interesting because it avoids mutating the original. To make it work for the OP's question you'll need to employ recursion, which is a little more complicated than the other answers because of the cloning effect at play. See an example here: [fiddle](https://jsfiddle.net/Lumh4yfk/1/) – pilchard Apr 23 '22 at 12:41

Delete property and its values in all the object

3 Answers3