An Easy to Use Weak Referenced Event Handler Factory for .NET 2.0

// ****************************************************************************
// Copyright Swordfish Computing Australia 2005                              **
// http://www.swordfish.com.au/                                              **
//                                                                           **
// Filename: Swordfish\Collections\WeakEventHandler.cs                       **
// Authored by: John Stewien of Swordfish Computing                          **
// Date: September 2005                                                      **
//                                                                           **
// - Change Log -                                                            **
// ****************************************************************************
// $Id: WeakEventHandler.cs,v 1.5 2005/10/11 01:43:22 stewienj Exp $

using System;
using System.Collections.Generic;
using System.Text;

namespace Swordfish.Collections
{
	/// <summary>
	/// Use this only when you know what you are doing. All weak event handlers
	/// must be removed before the host object is garbage collected, otherwise
	/// the underlying WeakReferenceToEventHandler will bomb when it next handles
	/// an event.
	/// </summary>
	/// <typeparam name="TEventArgs"></typeparam>
	public class WeakEventHandler<TEventArgs> : WeakEventHandlerInternal<TEventArgs> where TEventArgs : EventArgs
	{
		// ********************************************************************
		// Private Fields
		// ********************************************************************
		#region Private Fields

		/// <summary>
		/// Pre-calculated event handler for fast adding and removing of an event handler
		/// </summary>
		private EventHandler<TEventArgs> substituteHandler;

		#endregion Private Fields

		// ********************************************************************
		// Public Methods
		// ********************************************************************
		#region Public Methods

		/// <summary>
		/// Constructor. Initializes all the fields.
		/// </summary>
		/// <param name="eventSource"></param>
		public WeakEventHandler(EventHandler<TEventArgs> strongEventHandler) : base(strongEventHandler)
		{
			substituteHandler = new EventHandler<TEventArgs>(weakEventHandler.IntermediateEventHandler);
		}

		/// <summary>
		/// Implicit conversion allowing this object to be used in place of
		/// an event handler
		/// </summary>
		/// <param name="value"></param>
		/// <returns></returns>
		public static implicit operator EventHandler<TEventArgs>(WeakEventHandler<TEventArgs> weakEventHandler)
		{
			return weakEventHandler.substituteHandler;
		}

		#endregion Public Methods
	}
}