TypeScript Animal Class with Protected and Private Properties

TypeScript Classes and OOP : Exercise-20 with Solution

Write a TypeScript program that creates a class called Animal with the following properties and methods:

• protected name: string
• private age: number

The class should have a constructor that accepts name and age. Implement a method:

public introduce(): string that returns a string introducing the animal, including its name and age.

Ensure that the age property is accessible only within the class.

Sample Solution:

TypeScript Code:

class Animal {
  protected name: string;
  private age: number;

  constructor(name: string, age: number) {
    this.name = name;
    this.age = age;
  }

  public introduce(): string {
    return `Hi, I'm ${this.name}, and I am ${this.age} years old.`;
  }
}

// Example usage:
const animal = new Animal("Lion", 4);
console.log(animal.introduce()); // Output: Hi, I'm Lion, and I am 4 years old.

Explanations:

In the exercise above -

• First, we define an "Animal" class with a protected property 'name' and a private property 'age'.
• The constructor accepts 'name' and 'age' and initializes these properties accordingly.
• Next, we implement a public method "introduce()" that returns a string introducing the animal, including its name and age.
• The 'age' property is accessible only within the class, as requested.

Output:

"Hi, I'm Lion, and I am 4 years old."

TypeScript Editor:

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

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