protected override HistoryMemento OnUndo(ProgressEventHandler progressCallback)
{
List <HistoryMemento> actions = new List <HistoryMemento>(this.mementos.Count);
for (int i = 0; i < this.mementos.Count; i++)
{
HistoryMemento memento2 = this.mementos[(this.mementos.Count - i) - 1];
HistoryMemento item = null;
if (memento2 != null)
{
item = memento2.PerformUndo(progressCallback);
}
actions.Add(item);
}
return(new CompoundHistoryMemento(base.Name, base.Image, actions));
}
protected override HistoryMemento OnUndo()
{
List <HistoryMemento> redoActions = new List <HistoryMemento>(actions.Count);
for (int i = 0; i < actions.Count; ++i)
{
HistoryMemento ha = actions[actions.Count - i - 1];
HistoryMemento rha = null;
if (ha != null)
{
rha = ha.PerformUndo();
}
redoActions.Add(rha);
}
CompoundHistoryMemento cha = new CompoundHistoryMemento(Name, Image, redoActions);
return(cha);
}