Get variable by its name, which is stored in another variable

Question

How can I select an array variable by its name?

This is what I'm doing so far to get the content in a dynamic way:

const lib1 = ['banana', 'apple'],
      lib2 = ['audi', 'bmw'];
let   index = 1;

lib1[index] // result: apple

Now I need to select the array-variable also dynamical:

let library = 'lib2',
    index = 1;

library[index] // wrong - but should result 'bmw'

Why do you want to do this? If it's top level you can do `window[library][index]` — Luka Jacobowitz, Jun 24 '16 at 08:08
I need to do this in a function, and I do get the name as a parameter. — user3142695, Jun 24 '16 at 08:11

Nina Scholz · Accepted Answer · 2016-06-24T08:26:57.480

3

You could change the data structure a bit and access then with a key.

var lib1 = ['banana', 'apple'],
    lib2 = ['audi', 'bmw'],
    object = {lib1, lib2},
    index = 1,
    library = 'lib2';

console.log(object[library][index]);

edited Jun 24 '16 at 08:26

answered Jun 24 '16 at 08:11

Nina Scholz

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*"Advantage: it is not restricted to the global space"* - Local *or* global it is best to use an appropriate data structure for the job rather than separate variables, which in this case means organising each `libX` array within a single object just like you've shown. – nnnnnn Jun 24 '16 at 08:25

score 0 · Answer 2 · answered Jun 24 '16 at 08:18

0

You want to use variable as a execute code ,if so try with eval()

eval(library)[index];

answered Jun 24 '16 at 08:18

David Jaw Hpan

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Get variable by its name, which is stored in another variable

2 Answers2