My dilemma is that I have a few classes and I am trying to create a function that only accepts the classes themselves, not instances of the classes.
class Page1 {
}
class Page2 {
}
register(Page1);
register(Page2);
function Register(pageType){..}
Can someone help me figure out how to annotate the pageType parameter so that register(new Page1()); will result in an error?
Essentially, I am looking for the equivalent of this method in C#:
void Register(Type pageType){..}
After spending some time developing an IoC container for TypeScript at inversify.io, I discovered that using generics was the most effective approach:
class Page1 {
}
class Page2 {
}
interface Newable<T> {
new(...args: any[]): T;
}
function register<T>(pageType: Newable<T>){}
register<Page1>(Page1); // This works
register<Page2>(Page2); // This also works
register<Page1>(new Page1()); // Error message
register<Page2>(new Page2()); // Another error
If you want to streamline your code, consider creating an interface called 'Type' that extends Function and utilize it within your register method:
interface Type extends Function { }
function Register(pageType : Type ){..}
This will allow you to easily declare different page types and invoke the register method accordingly:
class Homepage {
}
class AboutPage {
}
register(Homepage);
register(AboutPage);
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