public PropertyChangeCommand(object target, string propertyName, object oldValue, object newValue)
{
_target = target;
_mementos = new PropertyMementos();
PropertyMemento memento = new PropertyMemento(propertyName, oldValue, newValue);
_mementos.AddPropertyMemento(memento);
}
public PropertyChangeCommand(object target, PropertyMemento memento)
{
_target = target;
_mementos = new PropertyMementos();
_mementos.AddPropertyMemento(memento);
}