Class ServiceCollectionExtensions

Namespace

Invex.Extensions.Hosting

Assembly

Invex.Extensions.Hosting.dll

Provides extension methods for Microsoft.Extensions.DependencyInjection.IServiceCollection that register a single implementation type under multiple service types ("forwarded" registrations) while sharing one instance per lifetime.

[PublicAPI]
public static class ServiceCollectionExtensions

Inheritance

object

ServiceCollectionExtensions

Examples

// MyService implements both IFoo and IBar; both resolve to the same singleton.
services.AddSingleton<IFoo, IBar, MyService>();

// All three resolve to the same object:
var foo = provider.GetRequiredService<IFoo>();
var bar = provider.GetRequiredService<IBar>();
var service = provider.GetRequiredService<MyService>();

// MyWorker implements IWorkerStatus and IHostedService; the running hosted service
// instance is also resolvable as IWorkerStatus.
services.AddHostedService<IWorkerStatus, MyWorker>();

Remarks

The standard AddSingleton/AddScoped methods create an independent instance per service type when the same implementation is registered multiple times. The overloads in this class instead register the implementation type once and forward each service type to it, so resolving any of the service types yields the same instance (per scope, for scoped registrations). TImplementation itself is also resolvable and returns that same instance. Singleton registrations share one instance for the application lifetime; scoped registrations share one instance within each scope, and different scopes receive different instances.

The AddHostedService overloads additionally register the implementation as an Microsoft.Extensions.Hosting.IHostedService, allowing other components to interact with the running hosted service through its service interfaces.

The container may dispose the shared instance more than once: it tracks every disposable object returned by a factory registration, and each forwarded service type is a factory registration. When the provider (or scope) is disposed, Dispose/DisposeAsync is called once for the TImplementation registration and once for each forwarded registration that was resolved, so implementations should make disposal idempotent.

Registrations are appended unconditionally, like the framework's own AddSingleton and AddScoped methods; they are not conditional TryAdd registrations.

In the net10.0 build, the TImplementation type parameter of every overload is annotated with [DynamicallyAccessedMembers] (DynamicallyAccessedMemberTypes.PublicConstructors), so the constructors required by the dependency injection container are preserved under trimming.

Methods

AddHostedService<TService, TImplementation>(IServiceCollection)

Adds a hosted service of the types specified in TService, with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddHostedService<TService, TImplementation>(this IServiceCollection serviceCollection) where TService : class where TImplementation : class, TService, IHostedService

Parameters

serviceCollection IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService

The type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

TImplementation is registered as a singleton and as a hosted service. Every service type and the hosted service resolve to the same shared instance, allowing other components to interact with the running hosted service through its service interfaces.

See Also

Singleton

AddHostedService<TService1, TService2, TImplementation>(IServiceCollection)

Adds a hosted service of the types specified in TService1, TService2, with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddHostedService<TService1, TService2, TImplementation>(this IServiceCollection serviceCollection) where TService1 : class where TService2 : class where TImplementation : class, TService1, TService2, IHostedService

Parameters

serviceCollection IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

TImplementation is registered as a singleton and as a hosted service. Every service type and the hosted service resolve to the same shared instance, allowing other components to interact with the running hosted service through its service interfaces.

See Also

Singleton

AddHostedService<TService1, TService2, TService3, TImplementation>(IServiceCollection)

Adds a hosted service of the types specified in TService1, TService2, TService3, with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddHostedService<TService1, TService2, TService3, TImplementation>(this IServiceCollection serviceCollection) where TService1 : class where TService2 : class where TService3 : class where TImplementation : class, TService1, TService2, TService3, IHostedService

Parameters

serviceCollection IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TService3

The third type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

TImplementation is registered as a singleton and as a hosted service. Every service type and the hosted service resolve to the same shared instance, allowing other components to interact with the running hosted service through its service interfaces.

See Also

Singleton

AddHostedService<TService1, TService2, TService3, TService4, TImplementation>(IServiceCollection)

Adds a hosted service of the types specified in TService1, TService2, TService3, TService4, with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddHostedService<TService1, TService2, TService3, TService4, TImplementation>(this IServiceCollection serviceCollection) where TService1 : class where TService2 : class where TService3 : class where TService4 : class where TImplementation : class, TService1, TService2, TService3, TService4, IHostedService

Parameters

serviceCollection IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TService3

The third type of the service to add.

TService4

The fourth type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

TImplementation is registered as a singleton and as a hosted service. Every service type and the hosted service resolve to the same shared instance, allowing other components to interact with the running hosted service through its service interfaces.

See Also

Singleton

AddHostedService<TService1, TService2, TService3, TService4, TService5, TImplementation>(IServiceCollection)

Adds a hosted service of the types specified in TService1, TService2, TService3, TService4, TService5, with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddHostedService<TService1, TService2, TService3, TService4, TService5, TImplementation>(this IServiceCollection serviceCollection) where TService1 : class where TService2 : class where TService3 : class where TService4 : class where TService5 : class where TImplementation : class, TService1, TService2, TService3, TService4, TService5, IHostedService

Parameters

serviceCollection IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TService3

The third type of the service to add.

TService4

The fourth type of the service to add.

TService5

The fifth type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

TImplementation is registered as a singleton and as a hosted service. Every service type and the hosted service resolve to the same shared instance, allowing other components to interact with the running hosted service through its service interfaces.

See Also

Singleton

AddScoped<TService1, TService2, TImplementation>(IServiceCollection)

Adds a scoped service of the types specified in TService1, TService2 with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddScoped<TService1, TService2, TImplementation>(this IServiceCollection services) where TService1 : class where TService2 : class where TImplementation : class, TService1, TService2

Parameters

services IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

All service registrations will share the same instance of the implementation type within a scope.

See Also

Scoped

AddScoped<TService1, TService2, TService3, TImplementation>(IServiceCollection)

Adds a scoped service of the types specified in TService1, TService2, TService3 with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddScoped<TService1, TService2, TService3, TImplementation>(this IServiceCollection services) where TService1 : class where TService2 : class where TService3 : class where TImplementation : class, TService1, TService2, TService3

Parameters

services IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TService3

The third type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

All service registrations will share the same instance of the implementation type within a scope.

See Also

Scoped

AddScoped<TService1, TService2, TService3, TService4, TImplementation>(IServiceCollection)

Adds a scoped service of the types specified in TService1, TService2, TService3, TService4 with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddScoped<TService1, TService2, TService3, TService4, TImplementation>(this IServiceCollection services) where TService1 : class where TService2 : class where TService3 : class where TService4 : class where TImplementation : class, TService1, TService2, TService3, TService4

Parameters

services IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TService3

The third type of the service to add.

TService4

The fourth type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

All service registrations will share the same instance of the implementation type within a scope.

See Also

Scoped

AddScoped<TService1, TService2, TService3, TService4, TService5, TImplementation>(IServiceCollection)

Adds a scoped service of the types specified in TService1, TService2, TService3, TService4, TService5 with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddScoped<TService1, TService2, TService3, TService4, TService5, TImplementation>(this IServiceCollection services) where TService1 : class where TService2 : class where TService3 : class where TService4 : class where TService5 : class where TImplementation : class, TService1, TService2, TService3, TService4, TService5

Parameters

services IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TService3

The third type of the service to add.

TService4

The fourth type of the service to add.

TService5

The fifth type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

All service registrations will share the same instance of the implementation type within a scope.

See Also

Scoped

AddSingleton<TService1, TService2, TImplementation>(IServiceCollection)

Adds a singleton service of the types specified in TService1, TService2 with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddSingleton<TService1, TService2, TImplementation>(this IServiceCollection services) where TService1 : class where TService2 : class where TImplementation : class, TService1, TService2

Parameters

services IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

All service registrations will share the same instance of the implementation type.

See Also

Singleton

AddSingleton<TService1, TService2, TService3, TImplementation>(IServiceCollection)

Adds a singleton service of the types specified in TService1, TService2, TService3 with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddSingleton<TService1, TService2, TService3, TImplementation>(this IServiceCollection services) where TService1 : class where TService2 : class where TService3 : class where TImplementation : class, TService1, TService2, TService3

Parameters

services IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TService3

The third type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

All service registrations will share the same instance of the implementation type.

See Also

Singleton

AddSingleton<TService1, TService2, TService3, TService4, TImplementation>(IServiceCollection)

Adds a singleton service of the types specified in TService1, TService2, TService3, TService4 with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddSingleton<TService1, TService2, TService3, TService4, TImplementation>(this IServiceCollection services) where TService1 : class where TService2 : class where TService3 : class where TService4 : class where TImplementation : class, TService1, TService2, TService3, TService4

Parameters

services IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TService3

The third type of the service to add.

TService4

The fourth type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

All service registrations will share the same instance of the implementation type.

See Also

Singleton

AddSingleton<TService1, TService2, TService3, TService4, TService5, TImplementation>(IServiceCollection)

Adds a singleton service of the types specified in TService1, TService2, TService3, TService4, TService5 with an implementation type specified in TImplementation to the specified Microsoft.Extensions.DependencyInjection.IServiceCollection.

public static IServiceCollection AddSingleton<TService1, TService2, TService3, TService4, TService5, TImplementation>(this IServiceCollection services) where TService1 : class where TService2 : class where TService3 : class where TService4 : class where TService5 : class where TImplementation : class, TService1, TService2, TService3, TService4, TService5

Parameters

services IServiceCollection

The Microsoft.Extensions.DependencyInjection.IServiceCollection to add the service to.

Returns

IServiceCollection

A reference to this instance after the operation has completed.

Type Parameters

TService1

The first type of the service to add.

TService2

The second type of the service to add.

TService3

The third type of the service to add.

TService4

The fourth type of the service to add.

TService5

The fifth type of the service to add.

TImplementation

The type of the implementation to use.

Remarks

All service registrations will share the same instance of the implementation type.

See Also

Singleton