SetWindowPos 窗口置顶与不置顶

if(m_ckTop.GetCheck())
::SetWindowPos(AfxGetApp()->m_pMainWnd->m_hWnd,HWND_TOPMOST,0,0,0,0,SWP_SHOWWINDOW|SWP_NOMOVE|SWP_NOSIZE);
    else
::SetWindowPos(AfxGetMainWnd()->m_hWnd,HWND_NOTOPMOST,0,0,0,0,SWP_SHOWWINDOW|SWP_NOMOVE|SWP_NOSIZE);