JavaScript继承-如何检查类类型？

Question

I have implemented inheritance in javascript like this: Parent class:

class Parent {
  constructor(data) {
    super(data);
    ...
  }
}
export default Parent;

and children classes: ChildA

class ChildA extends Parent {
  constructor(data) {
    super(data);
    ...
  }
}

export default ChildA;

and ChildB:

class ChildB extends Parent {
  constructor(data) {
    super(data);
    ...
  }
}

export default ChildB;

Now I got from server object which is mapped to one of these children base on flag. This flag is not in objects, so is possible how to later in code what of type is my object?

I tried myObj.constructor.name == 'ChildA' and myObj.constructor.name == 'ChildB' but it always returns false.

Answer 1

The simplest solution would be to have a type property on your classes that tells what kind of class each one is. It makes checking very simple.

A more involved solution would be to use Typescript , which has inheritance and typeguards built in.