How can we invoke the parent's method, when a child has a method with the same name in JavaScript? Anything like type casting in Java here? [duplicate]

问题

This question already has answers here:

How to call a parent method from child class in javascript? (8 answers)

Closed 10 days ago.

class Parent {
    constructor(x) {
        this.x = x;
    }

    present() {
        return `I have a ${this.x}`;
    }
}


class Child extends Parent {
    constructor(x, y) {
        super(x);
        this.y = y;
    }

    present() {
        return `${super.present()}, it is a ${this.y}`;
    }
}


child = new Child("Tinggu", "Winggu");
console.log(child.present()); // invokes the child version

How would I invoke the parent's method, from the child object? Type-Casting like Java doesn't seem to help.

回答1:

The methods inside the class get added to Parent.prototype. So, you could call the Parent's present function with the child object as this

Parent.prototype.present.call(child)

Here's a snippet:

class Parent {
    constructor(x) {
        this.x = x;
    }

    present() {
        return `I have a ${this.x}`;
    }
}


class Child extends Parent {
    constructor(x, y) {
        super(x);
        this.y = y;
    }

    present() {
        return `${super.present()}, it is a ${this.y}`;
    }
}

const child = new Child("Tinggu", "Winggu");
console.log(
  Parent.prototype.present.call(child)
);

来源：https://stackoverflow.com/questions/63167043/how-can-we-invoke-the-parents-method-when-a-child-has-a-method-with-the-same-n