The Object isSealed() method
New Courses Coming Soon
Join the waiting lists
Find out all about the JavaScript isSealed() method of the Object object
Accepts an object as argument, and returns true
if the object is sealed, false
otherwise. Objects are sealed when they are return values of the Object.seal()
function.
Example:
const dog = {}
dog.breed = 'Siberian Husky'
const myDog = Object.seal(dog)
Object.isSealed(dog) //true
Object.isSealed(myDog) //true
dog === myDog //true
In the example, both dog
and myDog
are sealed. The argument passed as argument to Object.seal()
is mutated, and can’t be un-sealed. It’s also returned as argument, hence dog
=== myDog
(it’s the same exact object).
→ Get my JavaScript Beginner's Handbook
→ Read my
JavaScript Tutorials
on The Valley of Code
→ Read my
TypeScript Tutorial
on The Valley of Code
Here is how can I help you:
- COURSES where I teach everything I know
- CODING BOOTCAMP cohort course - next edition in 2025
- BOOKS 16 coding ebooks you can download for free on JS Python C PHP and lots more
- Follow me on X