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JavaScript Objects

·216 words·2 mins·
Programming Javascript Objects Data-Structures Web-Development
Table of Contents

JavaScript Objects
#

An object is a collection of key-value pairs. In JavaScript, objects are used to represent complex data structures and are a fundamental part of the language.

Creating Objects
#

You can create an object using object literal syntax {} or the Object constructor.

// Object literal
let person = {
  firstName: "John",
  lastName: "Doe",
  age: 30
};
console.log(person);

// Object constructor
let car = new Object();
car.make = "Toyota";
car.model = "Camry";
console.log(car);

Accessing Properties
#

You can access object properties using dot notation or bracket notation.

let person = {
  firstName: "John",
  lastName: "Doe"
};

// Dot notation
console.log(person.firstName); // "John"

// Bracket notation
console.log(person["lastName"]); // "Doe"

Object Methods
#

An object can have methods, which are functions stored as object properties.

let person = {
  firstName: "John",
  lastName: "Doe",
  greet: function() {
    console.log(`Hello, my name is ${this.firstName} ${this.lastName}`);
  }
};

person.greet(); // "Hello, my name is John Doe"

The this Keyword
#

In an object method, this refers to the object itself. The value of this can change depending on how the function is called.

Object Destructuring
#

Destructuring makes it easy to extract properties from objects.

let person = {
  firstName: "John",
  lastName: "Doe",
  age: 30
};

const { firstName, age } = person;
console.log(firstName); // "John"
console.log(age); // 30

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