在一个＆＃39;这个＆＃39;中扩展2个班级。在javascript中

Question

我遇到了这个问题，我不知道如何从第三课扩展..所以我真的需要用参数＆＃39; TYPE＆＃39;来调用A类的方法，用C扩展，并且能够调用getType（）with class C.任何解决方案？

＆＃13;

＆＃13;

const TYPE = 'TYPE'

class A {
    constructor(type) {
        this.type = type;
    }
    
    getType() {
        return this.type;
    }
}

class B {
 constructor(id) {
        this.id = id;
    }
    
    getId() {
        return this.id;
    }
}

class C extends B {
    constructor(id) {
        super(id);
        
        //Here should be a function that should bind the method from class A
    }
}

const c = new C(1);
console.log(c.getId())
console.log(c.getType())

＆＃13;

＆＃13;

＆＃13;

Answer 1

＆＃13;

＆＃13;

const TYPE = 'TYPE'

class A {
    constructor(type) {
        this.type = type;
    }
    
    getType() {
        return this.type;
    }
    
    extend(extendedClassInstance){
      extendedClassInstance.type = this.type;
      extendedClassInstance.getType = this.getType.bind(extendedClassInstance)
    }
}

class B {
 constructor(id) {
        this.id = id;
    }
    
    getId() {
        return this.id;
    }
}

class C extends B {
    constructor(id) {
        super(id);
        (new A(TYPE)).extend(this) 
    }
}

const c = new C(1);
console.log(c.getId())
console.log(c.getType())

＆＃13;

＆＃13;

＆＃13;