INotifyPropertyChangedEx

INotifyPropertyChangedEx.cs

namespace ComponentModelEx
{
    public delegate void PropertyChangedExEventHandler(object sender, PropertyChangedExEventArgs e);

    public interface INotifyPropertyChangedEx
    {
        event PropertyChangedExEventHandler PropertyChangedEx;
    }
}

PropertyChangedExEventArgs.cs

namespace ComponentModelEx
{
    public class PropertyChangedExEventArgs : PropertyChangedEventArgs
    {
        public object OldValue { get; private set; }
        public object NewValue { get; private set; }

        public PropertyChangedExEventArgs(object oldValue, object newValue, string propertyName)
            : base(propertyName)
        {
            OldValue = oldValue;
            NewValue = newValue;
        }
    }
}