Using variable name in JS object?

Question

I defined a variable which will get user's input:

var input = USER_INPUT;

then, I create an object which will use this input as an variable name inside the object:

var obj = { input: Car.newCar(...)}

Then, I try to access the obj[input], but it returns to me undefined. Is it so that in javascript, I can not use variable as an object's variable name?

If I would like to define a object which has vary variable name and variable value, how can I do?

This is a possible duplicate of http://stackoverflow.com/questions/4119324/passing-in-dynamic-keyvalue-pairs-to-an-object-literal — rubiii, Apr 15 '11 at 07:39

score 2 · Answer 1 · answered Apr 15 '11 at 07:26

2

So I guess you want the store the input under a key named after the input itself.
You can assign the value returned by Car.newCar() by using the [] method:

var input = "some text";
var obj = {};

obj[input] = Car.newCar();

answered Apr 15 '11 at 07:26

rubiii

6,903
2
38
51

score 1 · Accepted Answer · edited Mar 06 '18 at 11:32

1

Sorry changed my answer after re-reading the question

var USER_INPUT = 'something';
var obj = {};
obj[USER_INPUT] = 'value';

obj.something ; //# => value
obj['something'] ; //# => value

obj[USER_INPUT]; //# => value

edited Mar 06 '18 at 11:32

Koustubh Kittur

43
8

answered Apr 15 '11 at 07:25

James Kyburz

13,775
1
32
33

no, he wants to access it like you do with PHP indices. input being a variable and not fixed string – JohnP Apr 15 '11 at 07:30
I know I was in the midst of changing my answer which I now have done. Note to self: More haste less spead :) – James Kyburz Apr 15 '11 at 07:32
here, have this +1 for your troubles :) – JohnP Apr 15 '11 at 07:34

Using variable name in JS object?

2 Answers2