Let's consider a scenario where we have an object with a specific property that is meant to reference another object, as shown below:
Object.defineProperty(parent, 'child', {
enumerable: true,
get: function() { return this._actualChild; },
set: function(v){
if(v && typeof v === 'object'){
this._actualChild = v;
} else {
throw new TypeError('child property must be an object!')
}
}
});
Is it possible to customize the behavior of this property when using JSON.stringify(), so that the .child property has its own unique toJSON method?
For example, after initializing the following:
var jill = {id: 3, name: 'Jill'};
parent.child = jill;
If we could somehow define the toJSON for parent.child to only return the id property of the child. This means that JSON.stringify(parent) would output:
{_actualChild: {id: 3, name: 'Jill'}, child: 3}
We can certainly define a toJSON method for the child object itself, but in that case we would get:
{_actualChild: 3, child: 3}
Ideally, I want to separate the property's toJSON method from the actual child object's toJSON method. Is there a way to achieve this?
It would be convenient if we could do something like this:
Object.defineProperty(o, 'child', {
enumerable: true,
get: function() {
return this._hiddenChild;
},
set: function(v){
if(v && typeof v === 'object'){
this._hiddenChild = v;
}
else {
throw new TypeError('child property must be an object!')
}
},
toJSON : function() {
return this._hiddenChild.id;
}
});
However, Object.defineProperty does not accept a toJSON descriptor.