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.

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

class SimpleCalculator { 
    z: number; 
    constructor() { } 
    addition(x: number, y: number) { 
        z = x + y; 
    } 
    subtraction(x: number, y: number) { 
        z = x - y; 
    } 
}  
class ComplexCalculator extends SimpleCalculator { 
    constructor() { super(); } 
    multiplication(x: number, y: number) { 
        z = x * y; 
    } 
    division(x: number, y: number) { 
        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.