您如何获取JavaScript中所有班级孩子的列表？

Question

I have a lot of classes, but for this question I'll simplify it a bit.

class A {

}

class B extends A {

}

class C extends A {

}

class D extends C {

}

Now my question is: how do you get a list of (all, not only direct) children of a class? So, A.getChildren() would be [B, C, D] and C.getChildren() would be [D] . By the way, I'm only looking for pure JavaScript solutions.

Maybe this isn't even possible and I need to approach this from a whole different way, like registering every class in its parent class.

So, is there a simple function (written or just built-in) that could do this, and if it's not even possible, in what other way should I solve this problem?

Answer 1

If you have control over A 's constructor and if every class is instantiated at least once, then you can put a line in the constructor which adds the child class to a Set :

 const classes = new Set(); class A { constructor() { classes.add(this.constructor); } } class B extends A { } class C extends A { } class D extends C { } new B(); new B(); new C(); new D(); console.log([...classes]);