Classes

I am a guy who believes that JavaScript is an object-based programming language and not an object-oriented programming language, and I know quite a lot of people who disagree with me.

In vanilla JavaScript, we have functions, which act like a class and exhibit prototype-based inheritance. In TypeScript/ES6, we have the class construct:

class Person { 
  name: string; 

constructor(personName: string) {  
this.name = personName;  
} 

getName { 
    return "The Name: " + this.greeting; 
}   
} 
// somewhere else 
arvind:Person = new Person('Arvind');

In the preceding example, we have defined a class named Person and we are defining the class constructor, which accepts the name on initialization of the class.

To initialize the class, we will invoke the class with a new keyword and pass in the name to the constructor. The variable that stores the instance of the class -- the object, arvind in the preceding example, can also be typed to the class. This helps in better understanding the possibilities of the arvind object.

Note: The classes in ES6 still follow Prototypal-based Inheritance and not the classical Inheritance model.