JSselect keys with variable of array

Question

Lets say I have an array:

var array = [
  {
   key1: {
     underkey1: {
       "somekey":"someValue"
     }
   },
  }
];

I know I can reach for key1 like this:

var theVar = "key1";
array[theVar];

But I want to reach underkey1 with one variable, like:

var theVar = "key1.underkey1";

From what I have tried I get undefined.

How can it be done?

you can declatre variable as var theVar=array.key1.underkey1; and now use that variable as theVar.someValue — Chandrakant Thakkar, Dec 07 '17 at 11:09

score 0 · Accepted Answer · answered Dec 07 '17 at 11:14

0

You can split that string into array of keys and then use reduce() to reach nested value.

var array = [{key1: {underkey1: "somevalue"},}];

var val = 'key1.underkey1'
  .split('.')
  .reduce((r, e, i, arr) => {
    return r[e] || (arr[i+1] ? {} : undefined)
  }, array[0])
  
console.log(val)

answered Dec 07 '17 at 11:14

Nenad Vracar

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Yes, that what I mean. Thanks. – Dec 07 '17 at 11:17
You're welcome, you can even pass index of object in array in string like so https://jsfiddle.net/Lg0wyt9u/2563/ – Nenad Vracar Dec 07 '17 at 11:18

score -1 · Answer 2 · edited Dec 07 '17 at 11:27

-1

try following:

var array = [
    {
        key1: {
            underkey1: "somevalue"
        },
    }
];

var theVar = "key1";
theVar2 = "underkey1"
array[0][theVar][theVar2];

edited Dec 07 '17 at 11:27

Tim Schmidt

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answered Dec 07 '17 at 11:11

Shyam

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The OP said they had `var theVar = "key1.underkey1";`, this ignores that. – Quentin Dec 07 '17 at 11:58

JSselect keys with variable of array

2 Answers2