Append element in JSobject

Question

I am trying to create a JS object which has this structure

{ node1: 
  [ 'test1.1',
   'test1.2'],
  node2:
   ['test2.1',
   'test2.2']
}

This is my code

    for (var k = 0; k < keys.length; i++){
            key = keys[k];
            var result = {};
            var r = [];
            for (var i = 0; i < elements.length; i++){
                r.push(elements[i]);
            }
            result[key] = r;
}

the result looks a bit different from my expectation and is not a valid JSON:

{ node1: 
   [ 'test1.1',
     'test1.2'] }
{ node2: 
   [ 'test2.1',
     'test2.2' ] }

I am not sure what is wrong about the code.

You are working exclusively with Javascript objects and then talk about JSON. The latter is inspired by the former, but they're not the same. Makes the question confusing. — RemcoGerlich, Aug 27 '18 at 13:18
But the problem is perhaps that you reset the result to an empty object each time you go through the outer loop. — RemcoGerlich, Aug 27 '18 at 13:19
Picking up on what RemcoGerlich said: JSON is a *textual notation* for data exchange. [(More here.)](http://stackoverflow.com/a/2904181/157247) If you're dealing with JavaScript source code, and not dealing with a *string*, you're not dealing with JSON. :-) — T.J. Crowder, Aug 27 '18 at 13:19
Please update your question with a [mcve] demonstrating the problem, ideally a **runnable** one using Stack Snippets (the `[<>]` toolbar button; [here's how to do one](https://meta.stackoverflow.com/questions/358992/)). — T.J. Crowder, Aug 27 '18 at 13:20
Welcome to Stack Overflow! Please take the [tour] (you get a badge!), have a look around, and read through the [help], in particular [*How do I ask a good question?*](/help/how-to-ask) — T.J. Crowder, Aug 27 '18 at 13:21
@T.J.Crowder: the first is one object, the second is two objects. Apparently he also prints inside the loop and then doesn't show us that. — RemcoGerlich, Aug 27 '18 at 13:21

Ankit Agarwal · Answer 1 · 2018-08-27T13:25:47.327

1

Declare var result = {}; outside the for loop and it will work as currently a new object is created inside the loop.

var result = {};
for (var k = 0; k < keys.length; k++) {
  key = keys[k];
  var r = [];
  for (var i = 0; i < elements.length; i++) {
    r.push(elements[i]);
  }
  result[key] = r;
}

You also have i++ in the first loop so change that to k++ otherwise there will be a infinite loop.

edited Aug 27 '18 at 13:25

answered Aug 27 '18 at 13:19

Ankit Agarwal

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This certainly starts them off the right way, but we have to know what `keys` and `elements` are. This will just put the same elements in both objects. – T.J. Crowder Aug 27 '18 at 13:24
Once they fix that, then if the OP wants to create JSON (since it seems he/she may be printing this out or something), they'd use `JSON.stringify(result)` to create the JSON to output. – T.J. Crowder Aug 27 '18 at 13:24

Append element in JSobject

1 Answers1