How to: Clear the Undo Stack

The following procedure below explains how to clear the undo stack.

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;
  }
  

See Also

Concepts

How to: Implement Undo Management