Fill an array in javascript inside an object

Question

i'm new to javascript and i have a little issue. I have an array like this:

name = ["Alex","John", "Mark"].

After that, i have and object with an array inside like this:

ObjectNames = {
  labels: []
}

I want to fill the labels array with the content of tha name array like this:

labels = [name[0], name[1], name[2]]

How to do this?

What you show works. You could also just have used `labels : name` inside the object unless you want to clone everything. — Shilly, Mar 10 '17 at 12:33
Possible duplicate of [Javascript fastest way to duplicate an Array - slice vs for loop](http://stackoverflow.com/questions/3978492/javascript-fastest-way-to-duplicate-an-array-slice-vs-for-loop) — user7393973, Mar 10 '17 at 13:23

Larpee · Accepted Answer · 2017-03-10T12:40:44.047

3

What you did in your question already solves your problem, but you can try this:

ObjectNames = {
    labels: names
}

This will make a copy of names and store it in labels.

Let me know if it works

Edit: As Andrew Li pointed out, there's no need to use slice, as JavaScript automatically creates a copy

edited Mar 10 '17 at 12:40

answered Mar 10 '17 at 12:36

Larpee

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Or just `slice()`. No argument required – Andrew Li Mar 10 '17 at 12:37
@Andrew Yes, I just realized that, thanks for clarifying. I've never been sure about when Javascript makes a copy and when it doesn't – Larpee Mar 10 '17 at 12:39

m87 · Answer 2 · 2017-03-10T12:41:38.687

2

You could do it like this :

var _name = ["Alex","John", "Mark"];
var ObjectNames = {
  labels: []
};
_name.forEach(function(e) {
  ObjectNames.labels.push(e);
});
console.log(ObjectNames.labels);

edited Mar 10 '17 at 12:41

answered Mar 10 '17 at 12:36

m87

4,287
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Anik Islam Abhi · Answer 3 · 2017-03-10T12:36:59.167

1

There are lots of way you can do that

Try like this

var ObjectNames = {
  labels: [name[0], name[1], name[2]]
}

or

var ObjectNames = {
  labels: name
}

or

var ObjectNames = {
  labels: name.slice()
}

or

ObjectNames = {
  labels: []
}

ObjectNames.labels=name ;

or like this

for(var i=0;i<name.length;i++)
  ObjectNames.labels.push(name[i])

or

name.forEach(x=> ObjectNames.labels.push(x))

edited Mar 10 '17 at 12:36

answered Mar 10 '17 at 12:33

Anik Islam Abhi

24,762
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i want to do this with a for loop not like that – user7334203 Mar 10 '17 at 12:34

Fill an array in javascript inside an object

3 Answers3