using System;

using System.ComponentModel;

​

public class Program

{

    public static void Main()

    {

        var foo = new Ticket();

        foo.ObjectState = ObjectState.Unchanged;

        Console.WriteLine(foo.ObjectState);

        foo.Division = new Division();

        foo.TicketType = new TicketType();

        Console.WriteLine(foo.ObjectState);

    }

​

}

​

public enum ObjectState { New, Unchanged, Changed, Deleted };

​

public abstract class BasicObject : System.Object, INotifyPropertyChanged

{

    public event PropertyChangedEventHandler PropertyChanged;

    protected void OnPropertyChanged(string name)

      {

          PropertyChangedEventHandler handler = PropertyChanged;

          if (handler != null)

          {

              handler(this, new PropertyChangedEventArgs(name));

          }

      }

    private ObjectState _objectState;

    public ObjectState ObjectState

    {

        get { return _objectState; }

        set { _objectState = value; }

    }

    public DateTime UpdateProperty(DateTime oldValue, DateTime newValue)

    {

        if (oldValue != newValue && ObjectState != ObjectState.New && ObjectState != ObjectState.Deleted)

        {

            ObjectState = ObjectState.Changed;

        }

        return newValue;

    }

    public bool UpdateProperty(bool oldValue, bool newValue)

    {

        if (oldValue != newValue && ObjectState != ObjectState.New && ObjectState != ObjectState.Deleted)

        {

            ObjectState = ObjectState.Changed;

        }

        return newValue;

    }

    public string UpdateProperty(string oldValue, string newValue)

    {

        if (oldValue != newValue && ObjectState != ObjectState.New && ObjectState != ObjectState.Deleted)

        {

            ObjectState = ObjectState.Changed;

        }

        return newValue;

    }

    public Division UpdateProperty(Division oldValue, Division newValue)

    {

        if (oldValue != newValue && ObjectState != ObjectState.New && ObjectState != ObjectState.Deleted)

        {

            ObjectState = ObjectState.Changed;

        }

        return newValue;

    }

    public TicketType UpdateProperty(TicketType oldValue, TicketType newValue)

    {

        if (oldValue != newValue && ObjectState != ObjectState.New && ObjectState != ObjectState.Deleted)

        {

            ObjectState = ObjectState.Changed;

        }

        return newValue;

    }

}

​

public abstract class BusinessObject : BasicObject

{

    private DateTime _dateCreated;

    private DateTime _dateLastModified;

    private DateTime? _dateDeleted;

    private bool _isDeleted;

    public BusinessObject() { SetProperties(); }

    private void SetProperties()

    {

        _dateCreated = DateTime.Now;

        _dateLastModified = DateTime.Now;

        _dateDeleted = null;

        _isDeleted = false;

    }

​

    public DateTime DateCreated 

    { 

        get { return _dateCreated; }

        set { _dateCreated = UpdateProperty(_dateCreated, value); OnPropertyChanged("DateCreated"); }

    }

    public DateTime DateLastModified 

    { 

        get { return _dateLastModified; }

        set { _dateLastModified = UpdateProperty(_dateLastModified, value); OnPropertyChanged("DateLastModified"); }

    }

    public bool IsDeleted 

    { 

        get { return _isDeleted; }

        set { _isDeleted = UpdateProperty(_isDeleted, value); OnPropertyChanged("IsDeleted"); } 

    }

}

​

​

public class Division : BusinessObject

{

    private string _name;

    public Division() : base()

    {

        SetProperties();

    }

    private void SetProperties()

    {

    }

    public Division(int _divisionId) : base()

    {

    }

    public string Name

    {

        get { return _name; }

        set { _name = UpdateProperty(_name, value); OnPropertyChanged("Name"); }

    }

}

​

public class TicketType : BusinessObject

{

    private string _name;

    public TicketType() : base()

    {

        SetProperties();

    }

    private void SetProperties()

    {

    }

    public TicketType(int _ticketTypeId) : base()

    {

    }

    public string Name

    {

        get { return _name; }

        set { _name = UpdateProperty(_name, value); OnPropertyChanged("Name"); }

    }

}

​

public class Ticket : BusinessObject

{

​

    private Division _division;

    private TicketType _ticketType;

    public Ticket() : base()

    {

        SetProperties();

    }

    private void SetProperties()

    {

    }

    public Ticket(int _ticketId) : base()

    {

    }

    public Division Division

    {

        get { return _division; }

        set { _division = UpdateProperty(_division, value); OnPropertyChanged("Division"); }

    }

    public TicketType TicketType

    {

        get { return _ticketType; }

        set { _ticketType = UpdateProperty(_ticketType, value); OnPropertyChanged("TicketType"); }

    }

}