The Object isFrozen() method
Find out all about the JavaScript isFrozen() method of the Object object
Accepts an object as argument, and returns true
if the object is frozen, false
otherwise. Objects are frozen when they are return values of the Object.freeze()
function.
Example:
const dog = {}
dog.breed = 'Siberian Husky'
const myDog = Object.freeze(dog)
Object.isFrozen(dog) //true
Object.isFrozen(myDog) //true
dog === myDog //true
In the example, both dog
and myDog
are frozen. The argument passed as argument to Object.freeze()
is mutated, and can’t be un-freezed. It’s also returned as argument, hence dog
=== myDog
(it’s the same exact object).
→ I wrote 17 books to help you become a better developer, download them all at $0 cost by joining my newsletter
→ JOIN MY CODING BOOTCAMP, an amazing cohort course that will be a huge step up in your coding career - covering React, Next.js - next edition February 2025