typescript - Why use a Service and Token / OpaqueToken to get the Window object in Angular -


i speaking colleague other day didn't code. in angular component access window object private mywindow = window;

he told me better way use service , token / opaquetoken (i have no idea opaquetoken is), so...

import {     injectable,     opaquetoken, } '@angular/core';  export const windowtoken = new opaquetoken('app.window');  @injectable() export class windowservice {     getwindow(): window {         return window;     } }

and can inject service , object so...

mywindow: window; constructor(@inject(windowtoken) windowref: windowservice) {         this.mywindow = windowref.getwindow(); }

it seems nice , clean don't understand advantage of using token (or token does) , service on assigning variable window object - can tell me why using service , token better practice?


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