create a new class using a string name in typescript

Question

I am writing an XML loader/parser (and new to typescript), I can load the XML fine, however I'm trying to dynamically parse the XML data back into a class/object. The problem is, I would like to create a class using a string variable; ie var classNameString:String = "className";

var newClass:any = new class(classNameString)

from my many searches of the internet it doesn't appear possible, and I'm going to have to hardcode the class names. Any help would be greatly appreciated.

It sounds same as [Dynamically loading a typescript class (reflection for typescript)](http://stackoverflow.com/a/15339429/629118). — Kazuki Sakamoto, Jan 08 '14 at 01:09

iCollect.it Ltd · Answer 1 · 2018-06-12T20:21:53.437

30

If you have a specific namespace, for all the class you want to create, you can do this:

var newClass: any = new (<any>MyNamespace)[classNameString](parametersIfAny);

and if they are in the default namespace you can simply use window:

var newClass: any = new (<any>window)[classNameString](parametersIfAny);

Update

You now need to have the <any> cast with latest TypeScript or you get an Error TS7017 Build:Element implicitly has an 'any' type because type '{}' has no index signature.

edited Jun 12 '18 at 20:21

answered Jan 16 '14 at 10:30

iCollect.it Ltd

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works great... nice and clean! – born2net Jan 09 '17 at 16:32
does this work also in nodejs? – Jaume Mussons Abad Nov 28 '17 at 17:16
@JaumeMussonsAbad: Try it and let me know. Assuming nodejs still uses standard instance creation it should work (of the namespace is correct). – iCollect.it Ltd Nov 30 '17 at 21:46
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My first result says it doesn't work in nodejs: "ReferenceError: window is not defined". – isgoed Apr 24 '18 at 14:22
@isgoed: This was never tested with nodejs so you may have additional namespaces present. Please ask a new question showing your code. Thanks – iCollect.it Ltd Apr 25 '18 at 14:15
Any way to accomplish this if the namespace is going to be part of the string? In my case a class will be passed as an option but it could belong to different namespaces – discodowney May 30 '19 at 20:28
@discodowney: Interesting problem. Have you tried passing the lot (e.g. `"namespace.classname"`) as the classname parameter value to the `window` version above and see what happens? – iCollect.it Ltd Jun 12 '19 at 09:12

create a new class using a string name in typescript

1 Answers1

Update