Database connection issues?

anhei1021

Please see the original code:
BOOL CMyApp :: InitInstance ()
{
   ...
AfxOleInit ();
pConn.CreateInstance (__ uuidof (Connection));
try
{
pConn-> Open ("Provider = Microsoft.Jet.OLEDB.4.0; Data Source = ki.mdb", "", "", adModeUnknown);
}
catch (_com_error e)
{
AfxMessageBox ("Database connection failed, confirm whether the database POP.mdb is in the current path!");
return false;
}
return FALSE;
}
extern CMyApp theApp;
void Show ()
{
        CString str;
str = "select * from Name";
        _RecordsetPtr m_pRs;
Ranch
    try
{
m_pRs = theApp.pConn-> Execute ((_ bstr_t) str, NULL, adCmdText);
}
catch (_com_error e)
{
AfxMessageBox (e.ErrorMessage ());
}
catch (...)
{
AfxMessageBox ("Error opening dataset 1!");
         }
Ranch
}
After running: "Invalid pointer" error displayed

anhei1021

According to my analysis, theApp.pConn was not found, but pConn has been defined.

anhei1021

I have understood that the code is misplaced. AfxOleInit (); and the following code should be placed on CMyDlg dlg;

pretendersam

It is still placed in the initialization of dloag, that is, in BOOL CYourDlg :: OnInitDialog ()

rsq666

It doesn't fit inside BOOL CMyApp :: InitInstance ().

joe2086

Use Coinintialize();
Your pConn is not created successfully