Inheritance in TypeScript

We just saw how to implement an inheritance in JavaScript using a prototype. Now, we will see how an inheritance can be implemented in TypeScript, which is basically ES6 inheritance.

In TypeScript, similar to extending interfaces, we can also extend a class by inheriting another class, as follows:

class SimpleCalculator { 
   z: number; 
    constructor() { } 
   addition(x: number, y: number) { 
        this.z = this.x + this.y; 
   } 
    subtraction(x: number, y: number) { 
        this.z = this.x - this.y; 
   } 
} 
  
class ComplexCalculator extends SimpleCalculator { 
    constructor() { super(); } 
   multiplication(x: number, y: number) { 
        this.z = x * y; 
   } 
    division(x: number, y: number) { 
        this.z = x / y; 
   } 
} 
var calculator = new ComplexCalculator(); 
calculator.addition(10, 20); 
calculator.Substraction(20, 10); 
calculator.multiplication(10, 20); 
calculator.division(20, 10); 

Here, we are able to access the methods of SimpleCalculator using the instance of ComplexCalculator as it extends SimpleCalculator.