Creating TypeScript Classes Dynamically - Totally based on Steve Fenton solution (Type Safe)

instance-loader.ts

// Credit
// https://www.stevefenton.co.uk/2014/07/creating-typescript-classes-dynamically
// https://gist.github.com/mfdeveloper/c337408608d6033fde967fc2e76b12c4


interface ObjectKeyString {
  [key: string]: any;
}

class InstanceLoader {
  static getInstance<T>(context: ObjectKeyString, name: string, ...args: any[]): T {
    const classRef: { new(...args: any[]): any; } = context[name];    
    if (!classRef) throw new Error(`The class '${name}' was not found`);
    let instance = Object.create(classRef.prototype);
    instance.constructor.apply(instance, args);
    return <T>instance;
  }
}

interface ConstructorTypes {
  userService: string;
  authService: string;
  info: Function;
}

class MyController {
  constructor(public userService: number, public authService: string) { }
  info(){ return "hey"}
}

const store = {
  MyController: MyController
}

var example = InstanceLoader.getInstance<ConstructorTypes>(store, 'MyController', 'user service', 'auth Service');
console.log(example.userService);
console.log(example.authService);
console.log(example.info());
    
// The output
// user service
// auth Service
// hey