gistfile1.cs

namespace INPC.Using.Dynamic.Proxy
{
	using System;
	using System.ComponentModel;
	using System.Reflection;
	using Castle.Core.Interceptor;
	using Castle.DynamicProxy;

	class Program
	{
		static void Main(string[] args)
		{
			var generator = new ProxyGenerator();

			var options = new ProxyGenerationOptions(new SetterProxyHook());
			options.Selector = new SetterInterceptorSelector();
			options.AddMixinInstance(new NotifyPropertyChanged());
			var proxy = generator.CreateClassProxy(typeof (SomeDto), options, new PropertyChangedInterceptor());
			(proxy as INotifyPropertyChanged).PropertyChanged +=
				((sender, e) => Console.WriteLine("Property " + e.PropertyName + " changed!"));
			var dto = proxy as SomeDto;
			dto.CreatedAt = DateTime.UtcNow;
			Console.ReadKey();
		}
	}

	public class SetterInterceptorSelector:IInterceptorSelector
	{
		public IInterceptor[] SelectInterceptors(Type type, MethodInfo method, IInterceptor[] interceptors)
		{
			if (MethodHelper.IsNotifierMethod(method))
				return new IInterceptor[0];
			return interceptors;
		}
	}

	public static class MethodHelper
	{
		public static bool IsNotifierMethod(MethodInfo info)
		{
			return info.DeclaringType.IsAssignableFrom(typeof(NotifyPropertyChanged));
		}
	}

	public class SetterProxyHook:IProxyGenerationHook
	{
		public bool ShouldInterceptMethod(Type type, MethodInfo methodInfo)
		{
			return IsSetter(methodInfo) || MethodHelper.IsNotifierMethod(methodInfo);
		}

		private bool IsSetter(MethodInfo info)
		{
			// this is very naive implementation
			return info.Name.StartsWith("set_");
		}

		public void NonVirtualMemberNotification(Type type, MemberInfo memberInfo)
		{
			
		}

		public void MethodsInspected()
		{
			
		}
	}

	public class PropertyChangedInterceptor:IInterceptor
	{
		public void Intercept(IInvocation invocation)
		{
			var notifier = invocation.Proxy as INotifier;
			invocation.Proceed();
			notifier.RaiseChanged(invocation.Proxy, invocation.Method.Name.Substring("set_".Length));
		}
	}

	public class NotifyPropertyChanged:INotifier
	{

		public event PropertyChangedEventHandler PropertyChanged = delegate { };
		public void RaiseChanged(object target,string propertyName)
		{
			PropertyChanged(target, new PropertyChangedEventArgs(propertyName));
		}
	}

	public interface INotifier:INotifyPropertyChanged
	{
		void RaiseChanged(object target, string propertyName);
	}

	public class SomeDto
	{
		public Guid Id { get; set; }

		public virtual DateTime? LastUpdatedAt { get; set; }

		public virtual DateTime? CreatedAt { get; set; }

		// etc...
	}
}