using System;
using Xceed.Wpf.DataGrid.ValidationRules;
using Xceed.Wpf.DataGrid;
using System.Globalization;
using System.Windows.Controls;
namespace Xceed.Wpf.Documentation
{
public class PeriodVSCompositionCountCellValidationRule : CellValidationRule
 {
   public override ValidationResult Validate( object value, CultureInfo culture,
                                              CellValidationContext context )
   {
     Row parentRow = context.Cell.ParentRow;
     int compositionCount;
     Period period;
     if( context.Cell.FieldName == "Period" )
     {
       period = ( Period )value;      
       compositionCount = ( int )parentRow.Cells[ "CompositionCount" ].Content;
     }
     else
     {
       period = ( Period )parentRow.Cells[ "Period" ].Content;
       compositionCount = ( int )value;
     }
     if( ( period == Period.Modern ) && compositionCount > 40 )
       return new ValidationResult( false, "Composition count must be less than 50 when the period is set to Modern." );
     return ValidationResult.ValidResult;
   }
 }
}

using System.ComponentModel;
using System.Windows.Media;
namespace Xceed.Wpf.Documentation
{
  public class Person: INotifyPropertyChanged, IDataErrorInfo
  {
    public Person( int personID, string firstName, string lastName, int age )
    {
      m_personID = personID;
      m_firstName = firstName;
      m_lastName = lastName;
      m_age = age;
    }
    public Person()
    {
    }
    public int PersonID
    {
      get
      {
        return m_personID;
      }
    }
    public string FirstName
    {
      get
      {
        return m_firstName;
      }
      set
      {
        if( m_firstName != value )
        {
          m_firstName = value;
          this.OnPropertyChanged( "FirstName" );
        }
      }
    }
    public string LastName
    {
      get
      {
        return m_lastName;
      }
      set
      {
        if( m_lastName != value )
        {
          m_lastName = value;
          this.OnPropertyChanged( "LastName" );
        }
      }
    }
    public int Age
    {
      get
      {
        return m_age;
      }
      set
      {
        if( m_age == value )
          return;
        m_age = value;
        this.OnPropertyChanged( "Age" );
      }
    }
    // INotifyPropertyChanged implementation
    public event PropertyChangedEventHandler PropertyChanged;
    private void OnPropertyChanged( string propertyName )
    {
      if( this.PropertyChanged != null )
        this.PropertyChanged( this, new PropertyChangedEventArgs( propertyName ) );
    }
    // IDataErrorInfo implementation
    [EditorBrowsable( EditorBrowsableState.Never ) ]
    [Browsable( false )]
    public string Error
    {
      get
      {
        return "IDataErrorInfo Error Message";
      }
    }
    [EditorBrowsable( EditorBrowsableState.Never )]
    [Browsable( false )]
    public string this[ string propertyName ]
    {
      get
      {
        if( propertyName == "Age" )
        {
          if( m_age < 18 )
            return "An employee must be 18 years or older.";
        }
        return string.Empty;
      }
    }  
    private string m_firstName = string.Empty;
    private string m_lastName = string.Empty;
    private int m_personID;
    private int m_age = 18;
  }
}