如何在 Angular/Typescript 中隔离私有静态函数？

Question

How to isolate private static functions of a class into another file.

In my component.ts I have lot of static functions and need to put them in another ts file for better readability purposes. How can I do that ?

Like we can put interfaces in another file and export them is there something similar for static functions too ?

Desired Result is I am able to call Component.foo() in component.ts file, but private static foo() exists in logic.ts file . Is it possible to do so ?

Answer 1

You can't do what you're asking.

You can easily create an external class for static files like:

export class Logic {
    public static foo() {
        console.log('foo');
    }
}

And then in component.ts you can call Logic.foo() just fine. However, you can't make foo private because then it's not available in Component. Also, while you rename Logic inside component or wherever else, ie

const LogicalFunctions = Logic;
LogicalFunctions.foo();

you can't reference them as a part of Component, a la Component.foo() .

Answer 2

It depends on what exactly you want to achieve.

You can have a file logic.ts:

export function foo(){ }

And then in your Component-class import this into a private static property if you don't mind an extra step in calling your functions.

import * as Logic from './Logic'

class Component
{
    private static Logic = Logic; 

    public DoStuff() {
        Component.Logic.foo();
    }
}


Component.Logic.foo(); // Not allowed

Of course anyone could reuse Logic.ts, but if your aim with "private" just is to limit the API of Component , it might be an idea.

And of course your foo won't have access to other private statics of Component, but if you need that I don't see the point in trying to separate your class into multiple files.