Maria D. Campbell

When an object property key is a string in JavaScript

Last night I learned the niftiest thing in my Evening JavaScript Intensive boot camp class about objects. Something I had never come across before, and that is also difficult to find in any official documentation. But it is a thing, and does exist!

Consider the following:

const cat = {
    name: 'Jack',
    age: 7,
    legs: 4,
    color: 'white',
    'favorite sports': ['football', 'soccer', 'baseball'],

Notice the last property key in the cat object? It consists of two separate words and is encapsulated in quotes. So how would we access that property key and its associated value? Only with bracket notation! If we wanted to access the favorite sport ‘baseball’, we would do the following:

console.log(cat['favorite sports'][2])

This would return baseball. Isn’t this is a much more descriptive way of naming object property keys? I think so. I went wild over this. The only place so far where I found any reference to this property key syntax was on StackOverflow:

And then a link to MDN within the StackOverflow thread:

Happy creative object property key naming!

Categorized under:javascript
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