Object Creation using Object.create() Method
The Object.create() method creates a new object using an existing object as its prototype. It enables prototype-based inheritance and allows properties to be defined while creating the object or later using Object.defineProperty() and Object.defineProperties().
What you'll cover
Learning objectives
- Understand Object.create()
- Understand Prototype Object
- Create Objects using Prototype
- Define Properties Dynamically
- Use Object.defineProperty()
- Use Object.defineProperties()
- Access Prototype Properties
Prerequisites
Related topics
Concept breakdown
Object.create()
The Object.create() method creates a new object using an existing object as its prototype.
Prototype Object
The prototype object acts as the parent object from which properties and methods are inherited.
Object.defineProperty()
Adds or modifies a single property of an object.
Object.defineProperties()
Adds or modifies multiple properties of an object simultaneously.
Object Creation using Object.create()
> { "firstName": "Sathesh", "lastName": "Kumar", "age": 30 }> [ "firstName", "lastName", "age" ]> "Monopoly IT Solutions"
Step by step
- 1
Create Prototype Object
Create companyObj containing companyName and companyAddress.
- 2
Create New Object
Create empObj using Object.create(companyObj).
- 3
Add Single Property
Use Object.defineProperty() to create the firstName property.
- 4
Add Multiple Properties
Use Object.defineProperties() to create lastName and age.
- 5
Display Object
Display the employee object in the browser console.
- 6
Retrieve Keys
Use Object.keys() to retrieve the object's own enumerable property names.
- 7
Access Prototype Property
Access companyName inherited from the prototype object.
Key takeaways
Key points
- Object.create() creates a new object using another object as its prototype.
- Inherited properties are available through the prototype chain.
- Object.defineProperty() defines a single property.
- Object.defineProperties() defines multiple properties.
- Object.keys() returns only the object's own enumerable properties.
- Prototype properties are not returned by Object.keys().
Advantages
- Supports Prototype-based inheritance.
- Creates lightweight objects.
- Easy to reuse existing objects.
- Provides fine-grained property control.
- Supports property descriptors.
Disadvantages
- Prototype chain may confuse beginners.
- Property descriptors require additional syntax.
- Inherited properties are not returned by Object.keys().
Employee Management System
Company information can be stored in a prototype object, while every employee object inherits company details and stores only employee-specific information.
Frequently asked questions
It creates a new object using another object as its prototype.
A prototype is the parent object from which another object inherits properties and methods.
Object.defineProperty() defines one property, whereas Object.defineProperties() defines multiple properties.
No. It returns only the object's own enumerable properties.
Yes. If the property is not found in the object, JavaScript searches the prototype chain.
Quick MCQ practice
1. Which method creates an object using another object as its prototype?
2. Which method defines multiple properties?
3. Which method returns only enumerable property names?
Practice on your own
Coding exercise
Student Prototype Object
Create a college object and create multiple student objects using Object.create(). Add properties using Object.defineProperties().
Assignment
- Create a Product prototype object.
- Create a Mobile object using Object.create().
- Add model, RAM and price using Object.defineProperties().
- Display inherited and own properties.
- Print all property names using Object.keys().
Tags
References
