How to create a new nested property in an object?

Question

If I create an object by doing let obj = {}, I can create a new link property by doing obj.link = 'test' and it works.

What if I want instead to create a nested property?

The code below gives an undefined error:

let obj = {}
obj.link.link = 'test'
console.log(obj.link.link)

What's the right way to do this?

Best one I think, can you make an answer so I can accept it please? — drake035
– drake035, Commented Feb 15, 2022 at 17:47

Mahesh Bongani · Accepted Answer · 2022-02-15 13:09:16Z

1

You're trying to access link property inside link, which is not there by the time. So you can do below things.

obj = {}
obj.link = {};
obj.link.link = 'test';
console.log(obj.link.link);
console.log(obj);

Or

 obj = {}
 obj.link = {link: 'test'}
 console.log(obj.link.link);
 console.log(obj);

answered Feb 15, 2022 at 13:09

Mahesh Bongani

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Comments

Nina Scholz · Accepted Answer · 2022-02-15 13:30:44Z

1

You need to have an object to address a property inside of an object.

Toassign use a default object and assign with the value to the last property.

let obj = {};

(obj.link ??= {}).link = 'test';

console.log(obj.link.link);
console.log(obj);

answered Feb 15, 2022 at 13:04

Nina Scholz

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