gistfile1.cs

namespace Castle.Windsor.Tests
{
	using System;
	using System.Collections.Generic;
	using Castle.Core;
	using Castle.MicroKernel;
	using Castle.MicroKernel.ComponentActivator;
	using Castle.MicroKernel.Registration;
	using Castle.MicroKernel.Resolvers;
	using Castle.MicroKernel.Tests.ClassComponents;
	using NUnit.Framework;

	[TestFixture]
	public class InjectIntoExistingInstanceTestCase
	{
		private IWindsorContainer container;
		
		[SetUp]
		public void SetUpTests()
		{
			container = new WindsorContainer();
			container.Register(Component.For<ResolveDependenciesOfInstance>());
		}
		
		[Test]
		public void CanDecorateExistingInstance()
		{
			container.Register(
				Component.For<DefaultMailSenderService>(),
				Component.For<DefaultTemplateEngine>()
			);
			
			var service = new DefaultSpamService();
			container.ResolveDependenciesOf(service);
			Assert.IsNotNull(service.MailSender);
			Assert.IsNotNull(service.TemplateEngine);
			Assert.AreSame(container.Resolve<DefaultMailSenderService>(), service.MailSender);
			Assert.AreSame(container.Resolve<DefaultTemplateEngine>(),service.TemplateEngine);
		}
	}
	
	public static class ResolveDependenciesOfExtension
	{
		public static void ResolveDependenciesOf(this IWindsorContainer container, object existingInstance)
		{
			var dependency = new Dictionary<string,object>{{"Castle.InstanceToResolveDependenciesOf", existingInstance}};
			container.Resolve("DecorateInstance:"+existingInstance.GetType().FullName,existingInstance.GetType(),new Arguments(dependency ));
		}
	}
	
	public class ResolveDependenciesOfInstance:ILazyComponentLoader 
	{
		public IRegistration Load(string key, Type service)
		{
			if(service == null || key == null || key != "DecorateInstance:"+service.FullName)
			{
				return null;
			}
			return Component.For(service).Named(key)
				.Activator<ExistingInstanceActivator>()
				.LifeStyle.Transient;
		}
	}
	
	public class ExistingInstanceActivator:DefaultComponentActivator
	{		
				public ExistingInstanceActivator(ComponentModel model, IKernel kernel,
										 ComponentInstanceDelegate onCreation,
										 ComponentInstanceDelegate onDestruction)
			: base(model, kernel, onCreation, onDestruction){}
		protected override object Instantiate(Castle.MicroKernel.Context.CreationContext context)
		{
			return context.AdditionalParameters["Castle.InstanceToResolveDependenciesOf"];
		}
	}
}