Angular 5, NullInjectorError: No Provider For Service


Answer :

You need to add TesteventService under providers under imports in your app.module.ts

providers: [   TesteventService  ]

Annotate your service class with -

@Injectable({ providedIn: 'root' })

The service itself is a class that the CLI generated and that's decorated with @Injectable(). By default, this decorator has a providedIn property, which creates a provider for the service. In this case, providedIn: 'root' specifies that Angular should provide the service in the root injector.


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