JavaScript Prototype

JavaScript is a programming language used for web development and other applications. JavaScript is an object-oriented language, which means that it is composed of objects and classes. JavaScript prototype is one of the core concepts of the language. It is used to create objects from classes and to extend existing objects. This tutorial will provide an overview of the JavaScript prototype and how to use it.

Why should you use it?

  • JavaScript prototype allows you to create objects from classes.
  • It allows you to extend existing objects.
  • It is a powerful tool for creating custom objects.

Prototype

JavaScript prototype is an object that contains properties and methods that are shared among all instances of a particular object. Every JavaScript object has a prototype property, which contains the prototype of that object. The prototype is a reference to another object and is used when a property or method is called on an object.

In JavaScript, objects are created by using the new operator. The new operator creates an instance of a particular object. When an object is created, the prototype of the object is set to the prototype of the constructor function that created the object. The prototype of the constructor function is the Object prototype.

The prototype of an object is used to extend the functionality of the object. For example, if you want to add a method to an object, you can add it to the object's prototype. The method will then be available to all instances of the object.

To create a new object with a custom prototype, you can use the Object.create() method. This method takes an object as an argument and returns a new object with the prototype set to the object passed in as an argument.

Example

In this example, we will create a constructor function and then create a new object using the Object.create() method. We will then add a method to the prototype of the constructor and then call the method on the new object.

// Create a constructor function
function Person(name, age) {
  this.name = name;
  this.age = age;
}

// Create a new object
let person = Object.create(Person.prototype);

// Add a method to the prototype
Person.prototype.sayHello = function() {
  console.log("Hello, my name is " + this.name);
};

// Call the method on the new object
person.sayHello();

In this example, we created a constructor function called Person. We then created a new object using the Object.create() method and set the prototype of the object to the prototype of the Person constructor. We then added a method to the prototype of the Person constructor and called the method on the new object.

As you can see, the prototype of an object is used to extend the functionality of the object. The prototype is a powerful tool that allows you to add methods and properties to an object without having to create new instances of the object.

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