借用构造函数,借助call或apply,使用SuPErclass构造函数,缺少函数复用

function Superclass(name = 'default') {
        this.name = name;
    }
    
    function Subclass(age = 22, name) {
        this.age = age;
        Superclass.call(this, name);
        this.say = function () {
            console.LOG(`this.name=${this.name}...this.age=${this.age}`);
        };
    }
    
    const test = new Subclass(23);
    test.say();
    console.log(`test instanceof Subclass`, test instanceof Subclass);
    console.log(`test instanceof Superclass`, test instanceof Superclass);
    console.log(test.__PRoto__.constructor);
    console.log(Subclass.prototype.constructor);

原型链继承,使用prototype指向Superclass对象,子类无法给父类传递参数,无法使用字面量添加新方法,所有子类对象共享父类所有方法和属性(引用类型)

    function Superclass(name = 'default') {
        this.name   = name;
        this.colors = ['r', 'y'];
    }

    function Subclass(age = 22) {
        this.age = age;
        this.say = function () {
            console.log(`this.name=${this.name}...this.age=${this.age}`);
        };
    }

    Subclass.prototype             = new Superclass();
    Subclass.prototype.constructor = Subclass;

    const test  = new Subclass(23);
    const test1 = new Subclass(24);
    test.colors.push('b');
    console.log(test.colors);
    console.log(test1.colors);
    test.say();
    test1.say();
    console.log(`test instanceof Subclass`, test instanceof Subclass);
    console.log(`test instanceof Superclass`, test instanceof Superclass);
    console.log(test.__proto__.constructor);
    console.log(Subclass.prototype.constructor);

组合继承,prototype+call/apply,借用构造函数对实例属性继承,prototype对共享方法继承,会调用两次父类构造函数

    function Superclass(name = 'default') {
        this.name = name;
    }

    Superclass.prototype.say = function () {
        console.log(this.name);
    };

    function Subclass(age = 22, name) {
        this.age = age;
        Superclass.call(name);
    }

    Subclass.prototype             = new Superclass();
    Subclass.prototype.constructor = Subclass;

    const test = new Subclass(23);
    test.say();
    console.log(`test instanceof Subclass`, test instanceof Subclass);
    console.log(`test instanceof Superclass`, test instanceof Superclass);
    console.log(test.__proto__.constructor);
    console.log(Subclass.prototype.constructor);

ES6 Class继承

    class Superclass {
        constructor(name = 'default') {
            this.name = name;
        }
    }
    class Subclass extends Superclass {
        constructor(age = 22, name) {
            super(name);
            this.age = age;
        }

        say() {
            console.log(`this.name=${this.name}...this.age=${this.age}`);
        }
    }

    const test = new Subclass(23);
    test.say();
    console.log(`test instanceof Subclass`, test instanceof Subclass);
    console.log(`test instanceof Superclass`, test instanceof Superclass);
    console.log(test.__proto__.constructor);
    console.log(Subclass.prototype.constructor);

Node util.inherITs;

    function Superclass(name = 'default') {
        this.name = name;
    }

    function Subclass(age = 22, name) {
        this.age = 22;
        Superclass.call(this, name);

        this.say = function () {
            console.log(`this.name=${this.name}...this.age=${this.age}`);
        };

    }

    require('util').inherits(Subclass, Superclass);

    const test = new Subclass(23);
    test.say();
    console.log(`test instanceof Subclass`, test instanceof Subclass);
    console.log(`test instanceof Superclass`, test instanceof Superclass);
    console.log(test.__proto__.constructor);
    console.log(Subclass.prototype.constructor);