The Object entries() method
By Flavio Copes
Learn how the JavaScript Object.entries() method returns an array of an object own [key, value] pairs, how it works with arrays, and how to count properties.
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Introduced in ES2017.
This method returns an array containing all the object own properties, as an array of [key, value] pairs.
Usage:
const person = { name: 'Fred', age: 87 }
Object.entries(person) // [['name', 'Fred'], ['age', 87]]
Object.entries() also works with arrays:
const people = ['Fred', 'Tony']
Object.entries(people) // [['0', 'Fred'], ['1', 'Tony']]
You can use it to count the number of properties an object contains, combined with the length property of the array.
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