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Create an object with dynamic keys

Written byPhuoc Nguyen
25 Feb, 2021
We often use the bracket notation to add a dynamic key to an object.
const key = 'ages';
const person = {
name: 'John Doe',

person[key] = 42;
ES6 allows us to do that in a declarative way as following:
const key = 'ages';
const person = {
name: 'John Doe',
[key]: 42,
Here is a simple usage. The sample code below returns the list of name and value of given input fields in a form:
// `formEle` is the form element
const data = [...formEle.querySelectorAll('input')].map((field) => {
return {
[field.getAttribute('name')]: field.getAttribute('value'),

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Phước Nguyễn