ES6 Class（类）的继承extends_es6 class extends

 ES6 Class（类）的继承通过extends关键字实现。在子类的方法中通过super关键字调用父类的方法。

class Person {
  constructor(name) {
    this.name = name;
  }
  sayHi() {
    console.log(`This is ${this.name}`);
  }
}
class Student extends Person {
  constructor(name, number) {
    super(name);  // 调用父类的constructor()
    this.number = number;
  }
  say() {
    super.sayHi();  // 调用父类的sayHi()
    console.log(`${this.name}'s number is ${this.number}`);
  }
}
const s = new Student('Lily', '1001');
s.say();  
 
// This is Lily
// Lily's number is 1001