Defining an object with a dynamic key in node js (javascript)

Question

I need to do this :

let obj = {}
obj.obj1 =  {'obj11':5}
console.log(obj.obj1.obj11)

//5

but I need to define the last key of the last object dynamically for example, something like this:

let obj = {}
key = 'obj11'
obj.obj1 =  { key :5}
console.log(obj.obj1.obj11)
// undefined

amrender singh · Answer 1 · 2018-06-20T18:15:56.323

1

To define computed properties in javascript objects use [].

Try the following:

let obj = {}
key = 'obj11'
obj.obj1 =  { [key] :5}
console.log(obj.obj1.obj11)

For reference : Reference

edited Jun 20 '18 at 18:15

answered Jun 20 '18 at 18:08

amrender singh

@CarlosFelipe Please mark as accepted if the answer helped you :-) – amrender singh Jun 20 '18 at 18:10
No, mark this answer as excepted *if* this is the best answer available. – Jonas Wilms Jun 20 '18 at 18:12

score 1 · Answer 2 · answered Jun 20 '18 at 18:09

Try

obj.obj1[key] = 5;

console.log(obj.obj1.obj11);

The object notation syntax does not support variables as keys directly, but java-script dictionaries do.

To evaluate the variable in the object notation syntax, use a bracket like so

obj.obj1 = {[key]: 5};

console.log(obj.obj1.obj11);

score 0 · Answer 3 · answered Jun 20 '18 at 18:09

0

You'll have to use bracket notation for this like

let obj = {}
key = 'obj11'
obj.obj1 =  { [key] :5}
console.log(obj.obj1.obj11)

answered Jun 20 '18 at 18:09

Muhammad Usman

score -1 · Answer 4 · answered Jun 20 '18 at 18:07

-1

Yes, you can do this:

console.log(obj.obj1[key]);

Every object in JavaScript is basically a dictionary so you can access it via the dictionary syntax.

answered Jun 20 '18 at 18:07

Keveloper

4 Answers4