public static void Undo(IUndoMarker marker)
{
Node node = (Node)marker;
Node cursor = currentNode;
while (cursor != null)
{
cursor.UndoItem.Undo();
if (cursor == node)
{
currentNode = cursor.Previous;
if (currentNode == null)
{
currentNode = new Node(new NoOperation())
{
Next = cursor
};
}
if (firstNode == cursor)
{
firstNode = currentNode;
}
return;
}
cursor = cursor.Previous;
}
throw new InvalidOperationException();
}
public static void Undo( IUndoMarker marker )
{
Node node = (Node) marker;
Node cursor = currentNode;
while ( cursor != null )
{
cursor.UndoItem.Undo();
if ( cursor == node )
{
currentNode = cursor.Previous;
if ( currentNode == null )
{
currentNode = new Node( new NoOperation() ) {Next = cursor};
}
if ( firstNode == cursor )
firstNode = currentNode;
return;
}
cursor = cursor.Previous;
}
throw new InvalidOperationException();
}
public static void Redo(IUndoMarker marker)
{
Node node = (Node)marker;
Node cursor = currentNode.Next;
while (cursor != null)
{
cursor.UndoItem.Redo();
if (cursor == node)
{
currentNode = cursor;
return;
}
cursor = cursor.Next;
}
throw new InvalidOperationException();
}
public static void Redo( IUndoMarker marker )
{
Node node = (Node) marker;
Node cursor = currentNode.Next;
while ( cursor != null )
{
cursor.UndoItem.Redo();
if ( cursor == node )
{
currentNode = cursor;
return;
}
cursor = cursor.Next;
}
throw new InvalidOperationException();
}
