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Check MFC samle Catalog2 in Database section
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Check MFC samle Catalog2 in Database section

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According to the docs, IsFieldNull takes one parameter, void *pv. &nbsp; What<br />
does pv want to be pointed at? &nbsp;The following doesn't work:<br />
<br />
CDBVariant &nbsp; &nbsp; varValue;<br />
<br />
m_pRecordSet-&gt;GetFieldValu<wbr />e(TableDat<wbr />a[0], varValue, SQL_C_SLONG);<br />
<br />
if (m_pRecordSet-&gt;IsFieldNull<wbr />(&amp;varValue<wbr />))<br />
// do something<br />
else<br />
// do something else<br />
<br />
Thanks.
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According to the docs, IsFieldNull takes one parameter, void *pv.   What
does pv want to be pointed at?  The following doesn't work:

CDBVariant     varValue;

m_pRecordSet->GetFieldValue(TableData[0], varValue, SQL_C_SLONG);

if (m_pRecordSet->IsFieldNull(&varValue))
// do something
else
// do something else

Thanks.

how do I use IsFieldNull?

Kernel and system programming is the process of creating the software necessary for a computer or device to function and operate other programs. Some operating systems (such as Microsoft Windows) are proprietary, but others, such as the various Linux distributions, are open source.