JSON.stringify - downcasting an object

Question

Is there a way to tell the stringify method to convert an object to a primitive datatype?

class Bar {
    constructor() {
        this.name = 'bar';
    }
}

const obj = {foo: new Bar};

JSON.stringify(obj);

// output:        '{foo: {name: 'bar'}}'
// wanted output: '{foo:'bar'}'

I've tried overriding toSting and valueOf methods but with no results

Bar.prototype.toString = function() {
    return this.name;
}

Bar.prototype.valueOf = function() {
    return this.name;
}

add a [`toJSON`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#tojson_behavior) to your class, that returns "bar". — ASDFGerte, Jul 16 '22 at 21:34

score 2 · Answer 1 · answered Jul 16 '22 at 21:36

2

Add toJSON prototype method in Bar class.

Bar.prototype.toJSON = function() {
    return this.name;
}

answered Jul 16 '22 at 21:36

hotbrainy

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JSON.stringify - downcasting an object

1 Answers1