public void SaveSelection()
{
SelectionUndoRecord selection = new SelectionUndoRecord(textEdit);
selection.Next = records;
records = selection;
}
public void CloseGroup()
{
if (groupStart == null)
{
Debug.Assert(false);
throw new InvalidOperationException();
}
if (groupStart == records)
{
// delete empty undo group to eliminate no-op entries on user's undo stack
records = records.Next;
return;
}
if (clearRedo)
{
textEdit.redo = null;
}
SelectionUndoRecord selection = new SelectionUndoRecord(textEdit);
selection.Next = records;
records = selection;
GroupEndUndoRecord end = new GroupEndUndoRecord(groupStart);
end.Next = records;
records = end;
groupStart = null;
}