Class ServiceProviderExtensions

Namespace

Cuemon.Extensions.DependencyInjection

Assembly

Cuemon.Extensions.DependencyInjection.dll

Extension methods for the IServiceProvider interface.

public static class ServiceProviderExtensions

Inheritance

object

ServiceProviderExtensions

Examples

The following example wraps the built service provider and then uses GetServiceDescriptors() to inspect the registrations that were added to the container. It registers singleton and scoped services in a ServiceCollection, builds the provider, and wraps it in a DelegatingServiceProvider. The wrapped provider's descriptors are queried for the registered types, and the results are written to the console, showing how to introspect service registrations at runtime.

using System;
using System.Linq;
using Cuemon.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection;

namespace Cuemon.Docs.Samples.DependencyInjection
{
    public static class ServiceProviderExtensionsExample
    {
        public static void Demonstrate()
        {
            var services = new ServiceCollection();
            services.AddSingleton<IClock, SystemClock>();
            services.AddScoped<IJobRepository, InMemoryJobRepository>();

            using var provider = services.BuildServiceProvider();
            var wrappedProvider = new DelegatingServiceProvider(provider);

            var descriptors = wrappedProvider.GetServiceDescriptors().ToList();

            Console.WriteLine(descriptors.Any(descriptor => descriptor.ServiceType == typeof(IClock)));
            Console.WriteLine(descriptors.Any(descriptor => descriptor.ServiceType == typeof(IJobRepository)));
        }

        public interface IClock
        {
        }

        public sealed class SystemClock : IClock
        {
        }

        public interface IJobRepository
        {
        }

        public sealed class InMemoryJobRepository : IJobRepository
        {
        }

        private sealed class DelegatingServiceProvider : IServiceProvider
        {
            private readonly IServiceProvider _provider;

            public DelegatingServiceProvider(IServiceProvider provider)
            {
                _provider = provider;
            }

            public object GetService(Type serviceType)
            {
                return _provider.GetService(serviceType);
            }
        }
    }
}

Methods

GetServiceDescriptors(IServiceProvider)

Gets an enumeration of ALL ServiceDescriptor instances from the specified provider.

public static IEnumerable<ServiceDescriptor> GetServiceDescriptors(this IServiceProvider provider)

Parameters

provider IServiceProvider

The IServiceProvider to extend.

Returns

IEnumerable<ServiceDescriptor>

An enumeration of ALL ServiceDescriptor instances from the specified provider.

Exceptions

NotSupportedException

This method does not support {providerType.FullName}; or a cyclic provider graph was detected.