Attribute-flavored Domain Driven Design

using System;
using System.Collections;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Runtime.Serialization;
using System.Xml.Serialization;
using Codebasement.DomainDrivenDesign.Basement.Attributes;
using Codebasement.DomainDrivenDesign.Basement.Basement;
using Codebasement.DomainDrivenDesign.Basement.Enums;
using Codebasement.DomainDrivenDesign.Model.ModelClasses;

namespace Codebasement.DomainDrivenDesign.Model.ModelClasses
{
    /// <summary>
    /// Contains a collection of <see cref="User"/> objects.
    /// </summary>
    [Serializable]
    [Description("Defines a collection of Users")]
    [XmlInclude(typeof (User))]
    [Relatable(typeof (User), 1, CardinalityType.ExactlyAsCardinality)]
    public sealed class Users : BasementObject
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="Users"/> class.
        /// </summary>
        public Users()
        {
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="Users"/> class.
        /// </summary>
        /// <param name="info">The info.</param>
        /// <param name="context">The context.</param>
        private Users(SerializationInfo info, StreamingContext context) : this()
        {
            ConstructParameters(info);
        }

        /// <summary>
        /// Overridable core validation of a <see cref="BasementObject"/>. Usage intended for specific business model validations.
        /// </summary>
        protected override void ValidateCore()
        {
            /* BUSINESS RULE : User names must be unique */

            ArrayList listUsers = new ArrayList();
            Collection<BasementObject> collection = GetSubItems(typeof (User), true);

            if (collection.Count > 0)
            {
                foreach (User item in collection)
                {
                    if (!listUsers.Contains(item.Name))
                        listUsers.Add(item.Name);
                    else
                    {
                        // already present
                        string message = string.Format("Non-unique User name {0} in Users group.",
                                                       item.Name);
                        string solution = string.Format("Change the Name property of the User item.");
                        ValidationResult result = new ValidationResult(this, ValidationResultType.Error, message,
                                                                       solution);

                        AddValidationResult(result);
                    }
                }
            }
        }
    }
}