吊死在这棵树上了.. 希望能详解

void CDlgLoadData::initTree(void)
{
    if(!connectDatabase())
        return;

    TV_INSERTSTRUCT tvInsert;            
    HTREEITEM            hParent, hItem;      
    tvInsert.item.mask=TVIF_TEXT|TVIF_IMAGE|TVIF_SELECTEDIMAGE;
    tvInsert.hInsertAfter=TVI_LAST;
    tvInsert.hParent=TVI_ROOT;
    tvInsert.item.pszText="数据库";
    tvInsert.item.cchTextMax=strlen("数据库");
    tvInsert.item.iImage=0;                                               //.
    tvInsert.item.iSelectedImage=0;

    hParent=m_tree.InsertItem(&tvInsert);     

    _variant_t   vtVal;
    CString     sVal;
    _RecordsetPtr rs;
    rs.CreateInstance(__uuidof(Recordset));
    try
    {                                                                                    
        sVal=CString("select * from ")+CString("layer");   
        rs->Open(sVal.GetBuffer(0),            //.数据库进行打开操作 x
            g_connGIS.GetInterfacePtr(),        
            adOpenDynamic,
            adLockOptimistic,
            adCmdText);
        sVal.ReleaseBuffer();        

        tvInsert.hParent=hParent;
        tvInsert.item.iImage=1;
        tvInsert.item.iSelectedImage=1;