objects.md

⚑ Objects:

Objects are generally Non-Primitive Data Types.

Objects in JavaScript are collections of key-value pairs, where the keys are properties and the values can be any data type. They represent real-world entities or concepts.

Objects are commonly used to represent the data structures, encapsulate properties and methods, and model real-world entities. They are essential for building complex real-word JavaScript applications.

☴ Overview:

1. Object properties and methods
2. Object creation
3. Constructors
4. Methods
5. Properties
6. Inheritance
7. Polymorphism
8. this keyword
9. Prototype inheritance

✦ Object Properties and Methods:

Properties: Key-value pairs that define the characteristics of an object. Methods: Functions defined within an object that operate on its properties.

✦ Object Creation:

• Literal notation:

let person = {
  name: "kumar",
  age: 30,
  greet: function() {
    console.log("Hello!");
  }
};

• Constructor function:

function Person(name, age) {
  this.name = name;
  this.age = age;
}

let person = new Person("kumar", 30);

✦ Constructors:

It is one type of functions used to create objects. It typically use the this keyword to initialize object properties.

✦ Methods:

It is one type of functions defined within an object. It can access and modify the object properties.

✦ Properties:

It is a key-value pairs that store data within an object.

✦ Inheritance:

Inheritance is a mechanism in object-oriented programming that allows to inherit properties and methods from one object (parent or base object) to another object (child or derived object).

Syntax:

class ChildClass extends ParentClass {
  // Constructor
  constructor() {
    super(); // Call the parent class's constructor
    // Additional properties or methods
  }
}

class Employee {
  constructor(name) {
    this.name = name;
  }

  details() {
    console.log("Details of Employee");
  }
}

class Manager extends Employee {
  details() {
    console.log("Name: " + this.name);
  }
}

let manager = new Manager("Kumar");
manager.details();

✦ Polymorphism:

Polymorphism is the ability of objects to respond to the same method call in different ways.

Syntax: (Overriding methods)

class ChildClass extends ParentClass {
  // Override the parent class's method
  method() {
    // Custom implementation
  }
}

class Employee {
  constructor(name) {
    this.name = name;
  }

  details() {
    console.log("Details of Employee");
  }
}

class Manager extends Employee {
  details() {
    console.log("Name: " + this.name);
  }
}

let manager = new Manager("Kumar");
manager.details();

✦ this Keyword:

This refers to the current object within a method.

✦ Prototype Inheritance:

Prototype Inheritance means that objects created using a constructor function inherit properties and methods from the constructor prototype.

Prototype: An object that serves as a template for other objects.

Creating custom prototypes: Syntax: (Modifying the prototype)

Object.prototype.myCustomMethod = function() {
  // Method implementation
};

Syntax: (Creating a custom prototype object)

function MyObject() {}

MyObject.prototype.myProperty = "value";
MyObject.prototype.myMethod = function() {
  // Method implementation
};

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