inject

Injects a token from the currently active injector. inject is only supported in an injection context. It can be used during:

• Construction (via the constructor) of a class being instantiated by the DI system, such as an @Injectable or @Component.
• In the initializer for fields of such classes.
• In the factory function specified for useFactory of a Provider or an @Injectable.
• In the factory function specified for an InjectionToken.
• In a stackframe of a function call in a DI context