WPF Control Factory

using System;
using System.Windows.Controls;
using Pfz.DataTypes;

namespace Pfz.WpfControls
{
	/// <summary>
	/// Control used to get passwords with confirmation.
	/// </summary>
	public class PasswordControl:
		UserControl,
		IValueControl,
		IValueContainer<PasswordString>
	{
		private PasswordBox fPassword1;
		private PasswordBox fPassword2;
		
		/// <summary>
		/// Creates a new password control.
		/// </summary>
		public PasswordControl()
		{
			fPassword1 = new PasswordBox();
			fPassword2 = new PasswordBox();
		
			var stackPanel = new StackPanel();
			stackPanel.Children.Add(fPassword1);
			stackPanel.Children.Add(fPassword2);
			Content = stackPanel;
		}

		/// <summary>
		/// Clears both password boxes.
		/// </summary>
		public void Clear()
		{
			fPassword1.Clear();
			fPassword2.Clear();
		}

		/// <summary>
		/// Gets or sets a value telling that this control is read-only.
		/// </summary>
		public bool IsReadOnly
		{
			get
			{
				return !IsEnabled;
			}
			set
			{
				IsEnabled = !value;
			}
		}
		
		/// <summary>
		/// Gets or sets the password of the password boxes.
		/// Note that an exception is thrown if the values are different.
		/// </summary>
		public string Value
		{
			get
			{
				string text = fPassword1.Password;
				if (text != fPassword2.Password)
					throw new ApplicationException("Password and confirmation must match!");
					
				if (text == "")
					return null;
				
				return text;
			}
			set
			{
				fPassword1.Password = value;
				fPassword2.Password = value;
			}
		}

		#region IValueContainer<PasswordString> Members
			PasswordString IValueContainer<PasswordString>.Value
			{
				get
				{
					return new PasswordString(Value);
				}
				set
				{
					Value = value.ToString();
				}
			}
		#endregion
		#region IValueContainer Members
			object IValueContainer.Value
			{
				get
				{
					return new PasswordString(Value);
				}
				set
				{
					PasswordString str = (PasswordString)value;
					Value = str.ToString();
				}
			}
		#endregion
	}
}