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ES6: classes constructor and super

Klasės sukūrimas:

class Holiday{}
console.log(Holiday.prototype);

Rezultatas:




Klasėje konstruktorius - 'planas' klasės.

class Holiday{
 constructor(destination, days){
  this.destination = destination;
  this.days = days;
 }

 info(){
  console.log(`${this.destination} will take ${this.days} days.`);
 }
}


const trip = new Holiday('Kathmandu, Nepal', 30);
console.log(trip.info());


Rezultatas:


ES6 klasės gali paveldėti tėvinės klasės savybe bei turėti naujų. Super - tėvinės klasės parametrai ir metodai.

//super class
class Holiday{
 constructor(destination, days){
  this.destination = destination;
  this.days = days;
 }

 info(){
  console.log(`${this.destination} will take ${this.days} days.`);
 }
}

//sub class
class Expedition extends Holiday {
 constructor(destination, days, gear){
  super(destination, days);
  this.gear = gear;
 }

 info(){
  super.info();
  console.log(`Bring your ${this.gear.join(" and your ")}`)
 }
}

const tripWithGear = new Expedition("Everest", 30, ["Sunglasses","Flags", "Camera"]);
tripWithGear.info();


Rezultatas:




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