2. Factories

In case your service should be resolved at by a more complex logic and ca not be simply added with only one implmentation you can use this feature.

You should implement

ITransientFactory<T>
IScopFactorye<T>
ISingletonFactory<T>

This will make the class as a factory and any TService will be injected using the method GetService implemented by the factory.

Implementation examples:

interface IMyService {}

class MyService1 : IMyService {}

class MyService2: IMyService {}

class MyServiceFactory: ITransientFactory<IMyService>{
  public IMyService GetService(){
    if(...) return new MyService1();
    return return new MyService2();
  }
}

Now anywhere IMyService is requested it will actually inject the MyService1 or MyService2.

If MyService1 or MyService2 have some dependencies themself you can use the Simple Injection like:

interface IMyService {}

class MyService1 : IMyService, ITransient<MyService1> {}

class MyService2: IMyService, ITransient<MyService2> {}

class MyServiceFactory: ITransientFactory<IMyService>{
  public MyServiceFactory(IServiceProvider serviceProvider)
  public IMyService GetService(){
    if(...) return serviceProvider.GetRequiredService<MyService1>();
    return return serviceProvider.GetRequiredService<MyService2>();
  }
}

Now you can use IMyService in other services and the Autojector will provide an instance of MyService.

class DependentService{
  public DependentService(IMyService myService){}
}