Object in Javascript

In Javascript, Objects are one of the fundamental data types and are used to represent and store collections of key-value pairs.

Objects can store complex data structures. such as attributes, methods etc.

Objects can be created using the object literal syntax {} or with the Object constructor.

Object Literal Syntax:

The most common way to create an object is using the object literal syntax, where we define key-value pairs inside curly braces `{}`.

Example:

const person = {
    name: "Alice",
    age: 23,
    isStudent: true,
    sayHello: function() {
        console.log("Hello, my name is " + this.name);
    }
};

Note:

"person" is an object with properties like "name", "age", "isStudent", and a method "sayHello".

Accessing Properties:

Example:

console.log(person.name);          // Outputs: Alice
console.log(person['age']);         // Outputs: 23
console.log(person.isStudent);  // Outputs: true
person.sayHello();                      // Outputs: Hello, my name is Alice

We can access object properties using dot notation (object.property) or square bracket notation (object['property']):

Example:

person.profession = "HR";
person['age'] = 28;

console.log(person.job);           // Outputs: HR
console.log(person.age);           // Outputs: 28

Adding and Modifying Properties:

Example:

delete person.age;

console.log(person.age);     // Outputs: undefined

We can add new properties or modify existing ones in the object.

Example:

const car = {
    brand: "Land Rover",
    model: "Defender",
    start: function() {
        console.log(this.brand + " " + this.model + " is starting.");
    },
    blowHorn: function() {
        console.log(" pee pee!");
    }
};

car.start();                        // Output: Land Rover Defender is starting.
car.blowHorn()                 // Output: pee pee!

Deleting Properties:

Example:

const person = new Object();
person.name = "Edward Collin";
person.age = 33;

console.log(person.title);          // Outputs: Edward Collin
console.log(person.age);           // Outputs: 33

We can delete properties using the `delete` keyword.

Object Methods:

Objects can contain functions as properties, which are then referred to as methods.

Object Constructor:

We can create objects using the "new" keyword and assign values to the attributes.

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