The Object isPrototypeOf() method
New Course Coming Soon:
Get Really Good at Git
Find out all about the JavaScript isPrototypeOf() method of an object
Called on an object instance, accepts an object as argument. If the object you called isPrototypeOf()
on appears in the prototype chain of the object passed as argument, it returns true
. Otherwise it returns false
.
Example:
const Animal = {
isAnimal: true
}
const Mammal = Object.create(Animal)
Mammal.isMammal = true
Animal.isPrototypeOf(Mammal) //true
const dog = Object.create(Animal)
Object.setPrototypeOf(dog, Mammal)
Animal.isPrototypeOf(dog) //true
Mammal.isPrototypeOf(dog) //true
→ 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