Copy properties between objects in JavaScript

Question

I have some JSON loaded into JavaScript. The two objects have different formats. However, I want to copy the information from one to the other.

var myCollection = {
  name: '2007',
  items: [
    {
      name: 'item 1'
    }
  ]
};

var data = {
  path: 'somewhere',
  children: []
};

I want to copy all of the properties of the data object into the myCollection.items[0] object. In reality, data will have more properties. So, I'm trying to figure out how to do this as dynamically as possible instead of the brute force approach.

I was thinking to do

myCollection.items[0] = data;

In my head, this approach doesn't work though.

What you have are **JavaScript** object. They have nothing to do with JSON. JSON is a textual data format, that looks similar. — Felix Kling, Jan 29 '16 at 15:04
@FelixKling thank you for correcting me. Always learning new things :) — JQuery Mobile, Jan 29 '16 at 15:05

Simon H · Accepted Answer · 2016-01-29T15:02:04.120

2

Just push

myCollection.items.push(data);

or, if you can use ES6 and don't want to mutate structures, I think you could:

let newItems = [...myCollection.items, data]
let newObj = Object.assign({}, myCollection, {items: newItems})

edited Jan 29 '16 at 15:02

answered Jan 29 '16 at 14:59

Simon H

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But that's not what the op wants? This will add the data to he array, not merge it with the fist object I the array. – Felix Kling Jan 29 '16 at 15:01
@FelixKling is correct. I'm trying to merge the data. Not just add items to the collection. – JQuery Mobile Jan 29 '16 at 15:05
Could you say what exactly you want the final outcome to look like with your example – Simon H Jan 29 '16 at 15:06

Copy properties between objects in JavaScript

1 Answers1