typescript extend class code example

Example 1: typescript extend interface

//declare interface to be extended
interface Vehicle {
  brand: string;
  plateNumber: number;
}

interface Car extends Vehicle {}

Example 2: typescript class interface

interface IPerson {
  name: string
  age: number
  hobby?: string[]
}

class Person implements IPerson {
  name: string
  age: number
  hobby?: string[]

  constructor(name: string, age: number, hobby: string[]) {
    this.name = name
    this.age = age
    this.hobby = hobby
  }
}

const output = new Person('john doe', 23, ['swimming', 'traveling', 'badminton'])
console.log(output)

Example 3: classes in typescript

class Info {
  private name: string ;
  constructor(n:string){
    this.name = n ;
  };
  describe(){
    console.log(`Your name is  ${this.name}`);
  }
}

const a = new Info('joyous');
a.describe();

Example 4: how to extend ts class

class Animal {
  move(distanceInMeters: number = 0) {
    console.log(`Animal moved ${distanceInMeters}m.`);
  }
}

class Dog extends Animal {
  bark() {
    console.log("Woof! Woof!");
  }
}

const dog = new Dog();
dog.bark();
dog.move(10);
dog.bark();Try

Example 5: ts extends

class Animal {
    name: string;
    constructor(theName: string) { this.name = theName; }
    move(distanceInMeters: number = 0) {
        console.log(`${this.name} moved ${distanceInMeters}m.`);
    }
}

class Snake extends Animal {
    constructor(name: string) { super(name); }
    move(distanceInMeters = 5) {
        console.log("Slithering...");
        super.move(distanceInMeters);
    }
}

class Horse extends Animal {
    constructor(name: string) { super(name); }
    move(distanceInMeters = 45) {
        console.log("Galloping...");
        super.move(distanceInMeters);
    }
}

let sam = new Snake("Sammy the Python");
let tom: Animal = new Horse("Tommy the Palomino");

sam.move();
tom.move(34);