Article ID: 321743
Article Last Modified on 3/21/2005
APPLIES TO
- Microsoft Visual Studio .NET 2002 Professional Edition
- Microsoft Visual Studio .NET 2003 Professional Edition
This article was previously published under Q321743
SUMMARY
This article summarizes the issues that developers have experienced when they port code from the Microsoft Visual C++ 6.0 OLE DB Provider Template classes to the Visual Studio .NET OLE DB Template classes.
MORE INFORMATION
The following list describes changes that may affect your code:
The Active Template Library (ATL) OLE DB Provider Templates that are included with Visual Studio .NET change the internal members, m_rgRowHandles and m_rgBindings, to CAtlMap objects. This new map object returns a CPair object for the Lookup method. You must reference the m_value member to get the object that you are looking up. For example:
m_rgRowHandles.Lookup(hRow)->m_valueVisual C++ 6.0 code uses the CAutoMemRelease class, which is replaced with the CComHeapPtr class in Visual Studio .NET.
If you implemented any of your own IRowsetNotify connection points, you may now have a conflict when you build. For example, if you implemented a method named Fire_OnRowChange, ATL includes additional code in the Atldb.h file that appears as follows:
__if_exists(T::Fire_OnRowChange)This causes a conflict because the ATL code thinks that you are using its new IRowsetNotify implementation and adds code when it should not. You receive the following compiler error message:
The ATL code should appear as follows:
__if_exists(ATL::T::Fire_OnRowChange)This is a bug.
- If you use the CSimpleArray class in your code, note that this class is replaced with CAtlArray.
REFERENCES
For more information, click the following article numbers to view the articles in the Microsoft Knowledge Base:
254633 OmniProv.exe - A sample ATL OLE DB provider for custom databases
321909 BUG: ATL OLE DB provider returns incorrect length for variable-length string field
Additional query words: C++ OLE DB Template classes
Keywords: kbinfo kbprovider kbmdacnosweep KB321743
