How to: Clear the Undo Stack
The following procedure below explains how to clear the undo stack.
To clear the undo stack use the IOleUndoManager::DiscardFrom method. The following is an example of this:
HRESULT CCmdWindow::ClearUndoStack() { HRESULT hr = S_OK; if (m_pUndoMgr == NULL) { IfFailGo(m_pTextLines->GetUndoManager(&m_pUndoMgr)); ASSERT(m_pUndoMgr != NULL, "",;); } IfFailGo(m_pUndoMgr->DiscardFrom(NULL)); Error: return hr; }