javascript es6类原型链修改

Question

I am trying to add class C to the prototype chain of class B

 class A { constructor() { this.a = 'a'; } } class B extends A { constructor() { super(); this.b = 'b'; } } class C extends A { constructor() { super(); this.c = 'c'; } } Object.setPrototypeOf(B.prototype, C.prototype); var a = new A(); var b = new B(); console.log(b instanceof C); console.log(b instanceof A); console.log(bc); 

The problem with the code is that super() call in the constructor of class B does not call the constructor of class C so the property c doesn't get added to the object. What am i doing wrong here?

Answer 1

super in the constructor is based on the classes prototype (not the classes prototype property's prototype):

 Object.setPrototypeOf(B.prototype, C.prototype);
 Object.setPrototypeOf(B, C);

That way you also get proper static method inheritance.