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What are classes in Javascript?

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Does Javascript have classes?

Classes are bits of code that encompass multiple objects, methods and allow manipulation for its member variables and functions. Within each language, a class has different syntax and the same holds true for Javascript.

In this language, a class is simply a variant of functions. Using the class functionality one can define the constructor and the prototype functions for the member objects in one encompassing block.

How do you create a class?

To create a class in Javascript, a few things should be noted:

  • A class is created using the keyword class as shown in the example below:
class Student{
// Elements within the class are declared and defined inside the brackets
}
  • A class has a default constructor which is empty but can also be defined within the class method. Unlike in other languages, to declare the constructor, Javascript has a specific keyword called constructor. The parameter(s) given to the constructor are then used to define elements within the class; class members.

  • The example below shows how this is done:

class Student{
//Declaring the constructor
constructor(name){this.name=name;}
}
  • Multiple methods can be defined in a Javascript class and they need not be separated by a , as shown in the example below:
class Student{
//This is the class constructor
constructor(name){this.name=name;}
//There is no comma between the two methods
//This is a method defined in the class; member method
displayStudentname(){console.log(this.name);}
}
  • An instance of a class is defined using the keyword new. To see how this is done, look at the code below:
class Student{
constructor(name){this.name=name;}
displayStudentname(){console.log(this.name);}
}
//Creating an instance of a class
let studentOne = new Student("JohnDoe");
studentOne.displayStudentname();

Note: All classes in Javascript use strict mode.

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