how to get json objects attribute using javascript

Question

Beginner at both JSON and javascript. I need a way to return the key subAttributeOne it self from a list of object instead of his value.

Following is example of a list,

var list = 
[
   {
   attribute1: "value",
   attribute2:[{subAttributeOne:"value",subAttributeTwo:"value"},{}]
   },
   //other objects
   {..}
]

I have tried following,

list[0].attribute2[1].subAttributeOne

it returns value but the result I need is subAttributeOne

Err… You already know you're looking for the string `"subAttributeOne"`… so what's there to look up in the array? It's not very clear what you're trying to accomplish. — deceze, Aug 24 '16 at 08:56

score 5 · Answer 1 · answered Aug 24 '16 at 08:55

5

With this:

Object.keys(list[0].attribute2[0])

you get

['subAttributeOne', 'subAttributeTwo']

answered Aug 24 '16 at 08:55

gianlucatursi

660
5
18

score 3 · Accepted Answer · edited May 23 '17 at 12:16

3

If you want keys from an object you can use object.keys that will bring back all the keys, but to define its position, in your case you can use like below:

Object.keys(list[0].attribute2[1])[0]

But the [0] doesn't work like an index because properties order in objects is not guarantee in JavaScript. To learn more about this I recommand you to read about : Does JavaScript Guarantee Object Property Order?

In this link you will find the definition of an Object from ECMAScript Third Edition:

4.3.3 Object

An object is a member of the type Object. It is an unordered collection of properties each of which contains a primitive value, object, or function. A function stored in a property of an object is called a method

edited May 23 '17 at 12:16

Community

1
1

answered Aug 24 '16 at 09:07

Simo

433
1
6
20

1

This working only because `subAttributeTwo` is bigger then `subAttributeOne`. The order of the keys is alphabetically – gianlucatursi Aug 24 '16 at 09:08
2

@t.gian18 The order is *arbitrary*, i.e. there is none. – deceze Aug 24 '16 at 09:26
1

http://stackoverflow.com/questions/5525795/does-javascript-guarantee-object-property-order – Xotic750 Aug 24 '16 at 09:36

how to get json objects attribute using javascript

2 Answers2