How to create class instance using class as variable?

Question

In typescript I pass whole class as reference MyClass to a function. How to create new instance of that class in that function?

export class MyClass {
}

createClass(MyClass);

function createClass(classReference) {
   const classInstance = new classReference();//not working
}

I need it because in angular's ModuleWithProviders I cannot call new MyClass().

Nitzan Tomer · Accepted Answer · 2017-07-24 08:34:25Z

2

It should look like this:

function createClass<T>(classReference: { new (): T }): T {
   return new classReference();
}

let a = createClass(MyClass); // type of a is MyClass

answered Jul 24, 2017 at 8:34

Nitzan Tomer

166k51 gold badges330 silver badges307 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

0mpurdy · Accepted Answer · 2017-07-24 08:34:04Z

0

In your ModuleWithProviders you could instead use:

{ provide: ProviderToReplace, useClass: MyClass }

answered Jul 24, 2017 at 8:34

0mpurdy

3,3531 gold badge22 silver badges29 bronze badges

Thanks for reply. I know that but that class is not a provider - it's array of classes with mostly data.

That makes sense, I'll leave this here in case it solves someone else's problem 😊