How can I initialize ADO in the ATL COM ?

[zyhu]

When I initialize ADO in the ATL COM with the following:

ADODB::_ConnectionPtr pConn;
pConn.CreateInstance(__uuidof(ADODB::Connection));

but the result is that the interface pointer pConn is NULL. Why?

 

[DannyB]

I think you should assign the result of your code to some variable. I'm not too strong with ATL though just read about lightly.

 

[zyhu]

Recently I found the following returned with the smart pointer successfully in Win98 but failed in WinNT4.0.
ADODB::_ConnectionPtr pConn;
pConn.CreateInstance(__uuidof(ADODB::Connection));

I don't know why it is.

 

[zyhu]

If use ADO to access database,the MDAC must be installed in the WinNT.
The following is used to initial ADO in the ATL COM:

_ConnectionPtr pObjADO_Connection = NULL;
hr = pObjADO_Connection.CreateInstance(__uuidof(Connection));
hr = pObjADO_Connection->Open( _bstr_t (L