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Practice

Object

An object is a collection of data represented as key-value pairs.

Here, the key is a string, and the value can be various data types (primitives, objects, functions, etc.).


Creating an object​

In JavaScript, an object is created using curly braces { }.

You can represent your wallet as an object like this:

Creating a Wallet Object
let wallet = {
  cash: 100,
  card: 'Visa',
  driverLicense: true,
};

cash, card, and driverLicense are properties of the object, and 100, 'Visa', true are the values of these properties.

Properties and values are connected with a colon (:), and each property is separated by a comma (,).


Accessing information from objects​

There are two ways to retrieve information from an object.


Using the dot (.) notation​

This is the most common method used to access the properties of an object.

Accessing Object Information with Dot Notation
let myMoney = wallet.cash; // 100

Using square brackets ([]) and keys​

This method is useful when the key is given as a variable or contains spaces or special characters.

Accessing Object Information with Square Brackets
let myCard = wallet['card']; // 'Visa'

Modifying and adding information to objects​

To modify or add information to an object, you can use both dot (.) notation and square brackets ([]).

Modifying and Adding Information to Objects
// Adding a new property
wallet['picture'] = 'family';

// Modifying an existing property's value
wallet.cash = 200;

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