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 void AddPropertyMemento(PropertyMemento memento)
{
if (memento == null)
{
throw new ArgumentNullException();
}
CheckAndCreateDictionary();
_propertyMementoDic[memento.PropertyName] = memento;
}
public void SetPropertyNewValue(string propertyName, object value)
{
CheckAndCreateDictionary();
PropertyMemento memento = null;
if (_propertyMementoDic.TryGetValue(propertyName, out memento))
{
if (memento != null)
{
memento.NewValue = value;
}
}
}
public object GetPropertyOldValue(string propertyName)
{
if (_propertyMementoDic == null)
{
return(null);
}
PropertyMemento memento = null;
if (_propertyMementoDic.TryGetValue(propertyName, out memento))
{
if (memento != null)
{
return(memento.OldValue);
}
}
return(null);
}
public PropertyChangeCommand(object target, PropertyMemento memento)
{
_target = target;
_mementos = new PropertyMementos();
_mementos.AddPropertyMemento(memento);
}