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<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>Hi everyone.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>I met a problem about IFeatureReader when I was writing
C# code.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>I rewrite the class MyFeatureReader derived from IFeatureReader
in C# which is the same as the class in GmlWriteTest.cpp in unit test of FDO with
the same name.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>Then I use XmlFeatureSerializer.XmlSerialize(featureReader,
featureWriter, flags), but always meet errors.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>I debug in the mgFdo, find error occurs here (in the red).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>[code]<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>System::Void NAMESPACE_FDO_XML::XmlFeatureSerializer::XmlSerialize(NAMESPACE_FDO_COMMANDS_FEATURE::IFeatureReader*
reader, NAMESPACE_FDO_XML::XmlFeatureWriter* writer,
NAMESPACE_FDO_XML::XmlFeatureFlags* flags)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>{<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:21.0pt'><font size=1 face=Arial><span
lang=EN-US style='font-size:9.0pt;font-family:Arial'>//The original code.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> //EXCEPTION_HANDLER(FdoXmlFeatureSerializer::XmlSerialize(static_cast<NAMESPACE_FDO_COMMANDS_FEATURE::IFeatureReaderImp*>(reader)->GetImpObj(),
writer->GetImpObj(), flags->GetImpObj())) <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-indent:21.0pt'><font size=1 face=Arial><span
lang=EN-US style='font-size:9.0pt;font-family:Arial'>//The full code same as the
original code<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 color=red face=Arial><span lang=EN-US
style='font-size:9.0pt;font-family:Arial;color:red'> NAMESPACE_FDO_COMMANDS_FEATURE::IFeatureReaderImp*
readerImp = static_cast<NAMESPACE_FDO_COMMANDS_FEATURE::IFeatureReaderImp*>(reader);<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 color=red face=Arial><span lang=EN-US
style='font-size:9.0pt;font-family:Arial;color:red'> GisPtr<FdoIFeatureReader>
uReader = readerImp->GetImpObj();<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> GisPtr<FdoXmlFeatureWriter>
uWriter = writer->GetImpObj();<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> GisPtr<FdoXmlFeatureFlags>
uFlags = flags->GetImpObj();<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> try <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> { <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> FdoXmlFeatureSerializer::XmlSerialize(uReader,
uWriter, uFlags); <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> } <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> catch(GisException*
e) <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> { <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> NAMESPACE_COMMON::Exception*
mgE = NAMESPACE_COMMON::Exception::Create(e); <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> e->Release();
<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> throw
mgE; <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'> }<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>}<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>[/code]<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>Because the reader is derived from IFearureReader, cast
it to a IFeatureReaderImp is not a right operation. Then use GetImpObj() will get
wrong pointer. This wrong point cause the error later. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>Is this a bug or I make some mistakes in my code?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>A bit of help would be greatly appreciated.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>Thanks<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>Kino<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span lang=EN-US><o:p> </o:p></span></font></p>
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