[CListCtrl]取得目前滑鼠所在位置的儲存格座標

目前是應用在CListCtrl::OnMouseMove()裡，用來取得目前滑鼠所在位置。

     const MSG* pMsg = this->GetCurrentMessage();  

     if ( pMsg == NULL ) {   

         return;    };  

     CPoint ptMsg = pMsg->pt;            //Get point from the message  

     this->ScreenToClient(&ptMsg);        //Convert the point's coords to be relative to this control  

     LVHITTESTINFO lvItemInfo;  

     lvItemInfo.pt = ptMsg;
  
     int nItem = this->SubItemHitTest(&lvItemInfo);  //Row Index - 0 base

     int nSubItem = 3;//lvItemInfo.iSubItem;                //Col Index - 0 base