C / C++ / MFC

void CMainFrame::OnDrawItem(int nIDCtl, LPDRAWITEMSTRUCT lpDrawItemStruct)
{
// TODO: Add your message handler code here and/or call default
if(nIDCtl == 0) //check if menu
{
	CDC dc;
	dc.Attach(lpDrawItemStruct->hDC); //wrap the HDC into a CDC
	dc.SaveDC();
        //draw the menu item
        .
        .
        .
	dc.RestoreDC(-1);  //restore the dc to the previous state
	dc.Detach();       //detach the HDC from the CDC to prevent its destruction
}
}

void CMyTreeCtrl::OnRButtonDown(UINT nFlags, CPoint point) 
{
    // disable this message to allow OnContextMenu to work
    
    //CTreeCtrl::OnRButtonDown(nFlags, point);
}

void CMyTreeCtrl::OnContextMenu(CWnd* pWnd, CPoint point) 
{
    CPoint pos;
    GetCursorPos(&pos);
    ScreenToClient(&pos);

    UINT flags = 0;
    HTREEITEM hItem = HitTest(pos, &flags);

    SetFocus();
    if (hItem != NULL)
    {
        SelectItem(hItem);

        CMenu menu;
        menu.CreatePopupMenu();

        VERIFY(menu.AppendMenu(MF_STRING, ID_MYID, "My Selection"));

        // display the menu
        GetCursorPos(&pos);        // need screen coordinates
        VERIFY(menu.TrackPopupMenu(TPM_LEFTALIGN | TPM_LEFTBUTTON, pos.x, pos.y, this));
    }
    else
    {
        TRACE("not on item\n");
    }
}

for ( int i = 1; i <= 2000; i++ )
  { 
  ostringstream strmName;
 
  strmName << "file" << i << ".txt" << ends;  
 
  ofstream outfile ( strmName.str().c_str() );
  
  // output to outfile here...
  }

GetParent()->SendMessage(LVN_ADDFILE, (WPARAM)(LPCTSTR) filename);

void MyDialog::MyFunc(WPARAM wParam, LPARAM lParam)
{
  AfxMessageBox ( (LPCTSTR) wParam);
}