Injectio - Source Generator for Dependency Injection


Source generator that helps register discovered services in the dependency injection container



Add package

Add the nuget package project to your projects.

dotnet add package Injectio

Prevent dependances from including Injectio

<PackageReference Include="Injectio" PrivateAssets="all" />

Registration Attributes

Place registration attribute on class. The class will be discovered and registered.

Attribute Properties

Property Description
ImplementationType The type that implements the service. If not set, the class the interface is on will be used.
ServiceType The type of the service. If not set, the Registration property used to determine what is registered.
Factory Name of a factory method to create new instances of the service implementation.
Duplicate How the generator handles duplicate registrations. See Duplicate Strategy
Registration How the generator determines what to register. See Registration Strategy

Duplicate Strategy

Value Description
Skip Skips registrations for services that already exists
Replace Replaces existing service registrations
Append Appends a new registration for existing services

Registration Strategy

Value Description
Self Registers each matching concrete type as itself
ImplementedInterfaces Registers each matching concrete type as all of its implemented interfaces
SelfWithInterfaces Registers each matching concrete type as all of its implemented interfaces and itself

Singleton services

public class SingletonService : IService { }

Explicit service type

[RegisterSingleton(ServiceType = typeof(IService))]
public class SingletonService : IService { }

Scoped Services

public class ScopedService : IService { }

Transient Services

public class TransientService : IService { }


[RegisterTransient(Factory = nameof(ServiceFactory))]
public class FactoryService : IFactoryService
    private readonly IService _service;

    public FactoryService(IService service)
        _service = service;

    public static IFactoryService ServiceFactory(IServiceProvider serviceProvider)
        return new FactoryService(serviceProvider.GetService<IService>());

Open Generic

[RegisterSingleton(ImplementationType = typeof(OpenGeneric<>), ServiceType = typeof(IOpenGeneric<>))]
public class OpenGeneric<T> : IOpenGeneric<T> { }

Register Method

When the service registration is complex, use the RegisterServices attribute on a method that has a parameter of IServiceCollection or ServiceCollection

public class RegistrationModule
    public static void Register(IServiceCollection services)
        services.TryAddTransient<IModuleService, ModuleService>();

Add to container

The source generator creates an extension method with all the discovered services registered. Call the generated extension method to add the services to the container. The method will be called Add[AssemblyName]. The assembly name will have the dots removed.

var services = new ServiceCollection();

Override the extension method name by using the InjectioName MSBuild property.

var services = new ServiceCollection();

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