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JavaScript Polymorphism

JavaScript Polymorphism

The JavaScript polymorphism is basically a core concept of object-oriented paradigm providing a way so that a single action can be performed in different forms. Polymorphism provides an ability to call the very same method on various JavaScript objects. Since JavaScript is not a type-safe language, users can pass any type of data members with the methods.

Examples of JavaScript polymorphism

1. Here is an example where a child class object invokes the parent class method:

<script>
class A
  {
     display()
    {
      document.writeln("space is invoked");
    }
  }
class B extends A
  {
  }
var b=new B();
b.display();
</script>
Output :space is invoked

2. In the following example, a child and parent class contains the same method. This example depicts that the object of child class invokes both classes method.

<script>
class A
  {
     display()
    {
      document.writeln("space is invoked<br>");
    }
  }
class B extends A
  {
    display()
    {
      document.writeln("spacex is invoked");
    }
  }

var a=[new A(), new B()]
a.forEach(function(msg)
{
msg.display();
});
</script>
Output :
space is invoked
spacex is invoked

3. Here is an example depicting with prototype-based approach.

<script>  
function A()  
{  
}  
A.prototype.display=function()  
{  
  return "A is invoked";  
}  
function B()  
{  
    
}  
  
B.prototype=Object.create(A.prototype);  
  
var a=[new A(), new B()]  
  
a.forEach(function(msg)  
{  
  document.writeln(msg.display()+"<br>");  
});  
</script>  
Output :
A is invoked
A is invoked