Implementing Model-View-Presenter in ASP.NET

using System;
using Model;
using Model.Data.Interfaces;
using Presentation.Interfaces;

namespace Presentation
{
	/// <summary>
	///		CustomersPresenter is the presenter in the event driven MVP relationship. 
	///		CustomersPresenter subscribes to events on its view and responds as
	///		necessary, telling the view what to do. It does not request information
	///		from the view, it only tell it what to do based on events raised by the view.
	/// 
	///		This MVP relationship is more of a Passive View.
	/// </summary>
	public class CustomersPresenter
	{
		private ICustomersView view = null;
		private IDomainDAO<ICustomer> model = null;

		// public event the ASPX page will register
		public event EventHandler<SingleValueEventArgs<string>> RequestCustomerEdit;

		public CustomersPresenter(ICustomersView view, IDomainDAO<ICustomer> model)
		{
			Check.IsNotNull(view, "view cannot be null");
			Check.IsNotNull(model, "model cannot be null");

			this.view = view;
			this.model = model;

			this.view.OnViewLoad += new EventHandler<SingleValueEventArgs<bool>>(OnViewLoadListener);
			this.view.RequestCustomerDetails += new EventHandler<SingleValueEventArgs<string>>(RequestCustomerDetailsListener);
			this.view.RequestCustomerEdit += new EventHandler<SingleValueEventArgs<string>>(RequestCustomerEditListener);
		}

		#region View Event Listeners
		private void OnViewLoadListener(object sender, SingleValueEventArgs<bool> isPostBack)
		{
			if (!isPostBack.Value)
			{
				// Set the view for the first time
				view.SetCustomers(model.FetchAllByName(true));
			}

			// Set this date on teh view every time
			view.SetRefreshTime(DateTime.Now);
		}

		private void RequestCustomerDetailsListener(object sender, SingleValueEventArgs<string> e)
		{
			// Set the view with updatd customer information
			string customerID = e.Value;
			ICustomer customer = model.FetchByID(customerID);
			view.SetCustomerDetails(customer);
		}

		private void RequestCustomerEditListener(object sender, SingleValueEventArgs<string> e)
		{
			// Raise our event. The ASPX page should be listening, but there is no guarantee.
			OnRequestCustomerEdit(e);
		}

		#endregion

		#region Presenter Raise Events
		/// <summary>
		///		Raise the RequestCustomerEdit event by invoking
		///		the delegates.
		/// </summary>
		public virtual void OnRequestCustomerEdit(SingleValueEventArgs<string> e)
		{
			EventHandler<SingleValueEventArgs<string>> eventHandler = RequestCustomerEdit;
			if (eventHandler != null)
			{
				eventHandler(this, new SingleValueEventArgs<string>(e.Value));
			}
		}
		#endregion
	}
}