import { Inject , Injectable , PLATFORM_ID } from '@angular/core' ; import { isPlatformBrowser , isPlatformServer } from '@angular/common' ; export interface IPlatformService { readonly isBrowser : boolean ; readonly isServer : boolean ; } @ Injectable ( ) export class PlatformService implements IPlatformService { constructor ( @ Inject ( PLATFORM_ID ) private platformId ) { } public get isBrowser ( ) : boolean { return isPlatformBrowser ( this . platformId ) ; } public get isServer ( ) : boolean { return isPlatformServer ( this . platformId ) ; } }