Multi tool use

Clash Royale CLAN TAG

Test the existence of a dynamically chosen class

I have data coming from an external source that I want to process. In order to do that, the objects I'm receiving are tagged with their original class name. Now I want to take that tag name and use it to populate a model in my own application. I'm stuck at the step where I check for that class having an equivalent in my codebase. Its going to look something like this:

this.objects.forEach((object) => {

if (typeof object.class_tag !== 'undefined') { //the problem line
//create class instance
}

});


In php I'd simply call class_exists to achieve this

<?php
if (class_exists($object->class_tag)) {}


What is the correct approach here?

1 Answer
1

I don't see the clear way to do this in a just one line.

One of the possible approaches is the way you register your existing classes.
For example if you use some kind of a namespace later on you can simply check the class for existance in the namespace.
Sample code:

namespace

class A {}
const a = "A"
const namespace = { A };

if (namespace[a]) {
// class exists, you can create object
const instance = new namespace[a]();
}


Probably, much better approach would be to make some service, that will registerClass, checkClass and createInstance for you. So your logic is wrapped in one place.

service

registerClass

checkClass

createInstance

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