发送单击事件失败

Question

   LRESULT hItem = 0;
   hItem = ::SendMessage(hWnd,TVM_GETNEXTITEM,TVGN_ROOT,NULL);
   hItem =::SendMessage(hWnd,TVM_SELECTITEM,TVGN_CARET,(LPARAM)hItem);
   hItem = ::SendMessage(hWnd,TVM_GETNEXTITEM,TVGN_NEXT,(LPARAM)hItem);

   
   
    ::SendMessage(hWnd,TVM_GETITEMRECT,NULL,(LPARAM)hItem);

     NM_TREEVIEW* pNMTreeView = (NM_TREEVIEW*)hWnd;
    CTreeCtrl m_TreeCtrl;
    m_TreeCtrl.Attach(hWnd);
   RECT   rc;  
   
   ::SendMessage(hWnd,TVM_GETITEMRECT,(WPARAM)FALSE,(LPARAM)&rc);

   ::SendMessage(hWnd,   WM_LBUTTONDBLCLK,(WPARAM)FALSE,(LPARAM)&rc);
   

   m_TreeCtrl.Detach();