TypeScript Basic Inheritance

TypeScript Classes and OOP : Exercise-9 with Solution

Write a TypeScript class called Animal with properties name and species. Implement a constructor that initializes these properties when an Animal object is created. Next, create a derived class Tiger that extends Animal. Add a method roar() to the Tiger class that prints a message indicating that the tiger is roaring.

Sample Solution:

TypeScript Code:

// Define the base class 'Animal'
class Animal {
  // Properties
  name: string;
  species: string;

  // Constructor for Animal
  constructor(name: string, species: string) {
    this.name = name;
    this.species = species;
  }
}

// Define the derived class 'Tiger' extending 'Animal'
class Tiger extends Animal {
  // Method to roar
  roar() {
    console.log(`The tiger named ${this.name} is roaring.`);
  }
}

// Create a Tiger object
const myTiger = new Tiger("Saber", "Bengal Tiger");

// Access and call the roar method
myTiger.roar(); // Output: The tiger named Saber is roaring.

Explanations:

In the exercise above -

• First, we define the base class "Animal" with the properties 'name' and 'species'. The constructor for the "Animal" class initializes these properties when an "Animal" object is created.
• Next we define the derived class "Tiger" that extends "Animal". The "Tiger" class includes a method "roar()" that uses the properties from the base class to print a message indicating that the tiger is roaring.
• Finally, we create an instance of the "Tiger" class called "myTiger" and call the "roar()" method, and display the roaring message in the console.

Output:

"The tiger named Saber is roaring."

TypeScript Editor:

See the Pen TypeScript by w3resource (@w3resource) on CodePen.

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