How do I cast a JSON Object to a TypeScript class?

I had the same issue and I have found a library that does the job : https://github.com/pleerock/class-transformer.

It works like this :

let jsonObject = response.json() as Object;
let fooInstance = plainToClass(Models.Foo, jsonObject);
return fooInstance;

It supports nested children but you have to decorate your class’s member.