JavaScript Object Methods
Object methods are actions that can be performed on objects.
A method is a function definition stored as a property value.
| Property | Value |
|---|---|
| firstName | John |
| lastName | Doe |
| age | 50 |
| eyeColor | blue |
| fullName | function() {return this.firstName + " " + this.lastName;} |
Example
const person = {
firstName: "John",
lastName: "Doe",
id: 5566,
fullName: function() {
return this.firstName + " " + this.lastName;
}
};
Try it Yourself »
firstName: "John",
lastName: "Doe",
id: 5566,
fullName: function() {
return this.firstName + " " + this.lastName;
}
};
In the example above, this refers to the person object:
this.firstName means the firstName property of person.
this.lastName means the lastName property of person.
Accessing Object Methods
You access an object method with the following syntax:
objectName.methodName()
If you invoke the fullName property with (), it will execute as a function:
If you access the fullName property without (), it will return the function definition:
Adding a Method to an Object
Adding a new method to an object is easy:
Example
person.name = function () {
return this.firstName + " " + this.lastName;
};
Try it Yourself »
return this.firstName + " " + this.lastName;
};
Using JavaScript Methods
This example uses the JavaScript toUpperCase() method to convert a text
to uppercase:
Example
person.name = function () {
return (this.firstName + " " + this.lastName).toUpperCase();
};
Try it Yourself »
return (this.firstName + " " + this.lastName).toUpperCase();
};
Learn More:
JavaScript Object Constructors
JavaScript Object Destructuring