Adding a key from a variable string (es6) when using spread syntax [duplicate]

Question

I would like to know if there is a clean way to set the value of a key from a string variable when using spread syntax in es6?

Something like the following:

let keyVar = 'newKey'
let newObject = {keyVar:{some:'json'},...oldObject}

But this leads to:

{"keyVar":{"some":"json"}, ... }

rather than:

{"newKey":{"some":"json"}, ... }

FYI, "spread properties" are not part of ES6. They are currently a proposal, i.e. an experimental feature. But it doesn't change how to set the property anyway. It also has nothing to do with JSON. — Felix Kling
– Felix Kling, Commented Dec 22, 2016 at 22:58

Michał Perłakowski · Accepted Answer · 2016-12-22 22:23:26Z

62

const keyVar = 'newKey';
const newObject = { [keyVar]: { some: 'json' } };
console.log(newObject);

answered Dec 22, 2016 at 22:23

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1 Comment

Perfect. thank you