VC弹出右键菜单

void CMailSearchDlg::PopupMenu()
{
    CPoint point2;
    ::GetCursorPos(&point2);
    CPoint menupoint = point2;
    ScreenToClient(&point2);
    CMenu menu;
    menu.LoadMenu(IDR_MENU_EMAILLIST);
    CMenu *pSubMenu = menu.GetSubMenu(0);
    if (pSubMenu != NULL)
    {
        int nSelectCount = m_wndEmailList.GetSelectedCount();
        if ( nSelectCount == 0 )
        {
            pSubMenu->EnableMenuItem(ID_MENU_COPYEMAIL, MF_GRAYED | MF_BYCOMMAND | MF_DISABLED);
        }
        if ( 0 == m_wndEmailList.GetItemCount() )
        {
            pSubMenu->EnableMenuItem(IDC_BUTTON_EXPORT, MF_GRAYED | MF_BYCOMMAND | MF_DISABLED);
            pSubMenu->EnableMenuItem(IDC_BUTTON_EMPTY, MF_GRAYED | MF_BYCOMMAND | MF_DISABLED);
        }
        pSubMenu->TrackPopupMenu(TPM_RIGHTBUTTON, menupoint.x, menupoint.y, this);
        pSubMenu->DestroyMenu();
    }
}