javascript - 类继承 - 添加参数而不重写父构造函数参数

Question

我想扩展以下类(class):

class Person {
    constructor(name, age) {
        this._name = name;
        this._age = age;
    }
  
    get name() {
        return this._name;
    }
  
    get age() {
        return this._age;
    }
}

...通过添加 sport 及其 getter:

class Athlete extends Person {
    constructor(name, age, sport) {
        super();
        this._name = name;
        this._age = age;
        this._sport = sport;
    }
  
    get sport() {
        return this._sport;
    }
}

虽然上述方法有效，但我想避免重复基父构造函数的参数。以下方法不起作用:

class Athlete extends Person {
    constructor(sport) {
        super();
        this._sport = sport;
    }
  
    get sport() {
        return this._sport;
    }
}

let athlete = new Athlete('Peter', 29, 'cricket');
console.log(athlete.name, athlete.age, athlete.sport); // name and age are not inherited, is returned 'undefined'

那么，如何在不重写基类字段的情况下向子类添加字段呢？

Answer 1

您需要传递参数，但可以通过将它们传递给 super() 来避免分配所有参数:

class Athlete extends Person {
    constructor(name, age, sport) {
        super(name, age); // pass arguments to super()
        this._sport = sport;
    }
  
    get sport() {
        return this._sport;
    }
}

let athlete = new Athlete('Peter', 29, 'cricket');
console.log(athlete.name, athlete.age, athlete.sport);