RE: Bug in MSXML / XML Parser .Net

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From: Michael (Michael_at_discussions.microsoft.com)
Date: 10/06/04 

Date: Wed, 6 Oct 2004 06:11:01 -0700

As a workaround I used generate-id() function in Muenchian method instead of
count():
Something with numeric predicate I think.

<xsl:for-each select="Document[@filter='' or
@filter=$filter]/Article[generate-id()=generate-id(key('by-info',@info)[@filter='' or @filter=$filter])]">

Now it works as it should.

--Michael

"Michael" wrote:

> I have figured out that this is a parser issue.
> My IE is using version 3.0 set as default in registry.
>
> http://www.perfectxml.com/articles/xml/XSLTInMSXML.asp
>
> There must be a way to set this in a namespace so, IE does understand what
> processor to use.
>
> /Michael
>
> "Michael" wrote:
>
> > Hi,
> >
> > I have a problem parsing XML file using XSLT style*** by using :
> >
> > using System.Xml;
> > using System.Xml.XPath;
> > using System.Xml.Xsl;
> >
> > // load Xsl style***
> > XslTransform myXslTrans = new XslTransform() ;
> > myXslTrans.Load(Server.MapPath("style***.xslt"));
> >
> > // load the Xml doc
> > XPathDocument myXPathDoc = new XPathDocument(Server.MapPath("file.xml"));
> >
> > // write the transformed result
> > XmlTextWriter writer = new XmlTextWriter(Server.MapPath("result.xml"), null);
> >
> > // do the actual transform of Xml
> > // pass XmlResolver to Transform() method
> > myXslTrans.Transform(myXPathDoc, null, writer, null);
> > writer.Close();
> >
> >
> > XML file
> >
> > <?xml version="1.0" encoding="utf-8"?>
> >
> > <Documents>
> > <Document chapter="1" title="title 1" href="file1.xml" filter="">
> > <Article title="1.1" info="sub" filter="food"/>
> > <Article title="1.2" info="main" filter="food"/>
> > </Document>
> > <Document chapter="2" title="title 2" href="file2.xml" filter="drink">
> > <Article title="2.1" info="sub" filter="drink"/>
> > <Article title="2.2" info="main" filter="food"/>
> > </Document>
> > </Documents>
> >
> >
> > XSLT style***
> >
> > <?xml version='1.0' encoding='UTF-8'?>
> >
> > <xsl:style*** version="1.0"
> > xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
> >
> > <!-- using muenchian method group by an attribute by asigning a unique
> > key to each element -->
> >
> > <xsl:output method="html" version="1.0" encoding="UTF-8" indent="yes"/>
> >
> > <!-- xsl:key name="by-proctype" match="Doc" use="@proceduretype"/ -->
> >
> > <!-- define info key -->
> > <xsl:key name="by-info" match="Article" use="@info"/>
> >
> > <!-- put the filter string in a global parameter -->
> > <xsl:param name="filter" select="'food'"/>
> >
> > <xsl:template match="Documents"><!-- @filter='' will be true if it is
> > there and empty or if it is not there at all) -->
> >
> > <documents>
> > <xsl:for-each select="Document[@filter='' or
> > @filter=$filter]/Article[count(.|key('by-info',@info)[@filter='' or
> > @filter=$filter][1])=1]">
> > <document name="{@info}"><xsl:copy-of
> > select="key('by-info',@info)[@filter=$filter]"/></document>
> > </xsl:for-each>
> > </documents>
> > </xsl:template>
> >
> > </xsl:style***>
> >
> >
> > Exception Details:
> >
> > System.NullReferenceException: Object reference not set to an instance of an
> > object."
> >
> > Stack Trace:
> >
> > [NullReferenceException: Object reference not set to an instance of an
> > object.]
> > System.Xml.XPath.FilterQuery.SetXsltContext(XsltContext input)
> > System.Xml.XPath.FilterQuery.SetXsltContext(XsltContext input)
> > System.Xml.XPath.MergeFilterQuery.SetXsltContext(XsltContext input)
> > System.Xml.XPath.OrQuery.SetXsltContext(XsltContext context)
> > System.Xml.XPath.MethodOperand.SetXsltContext(XsltContext context)
> > System.Xml.XPath.LogicalExpr.SetXsltContext(XsltContext context)
> > System.Xml.XPath.FilterQuery.SetXsltContext(XsltContext input)
> > System.Xml.XPath.MergeFilterQuery.SetXsltContext(XsltContext input)
> > System.Xml.XPath.CompiledXpathExpr.SetContext(XmlNamespaceManager
> > nsManager)
> > System.Xml.Xsl.Processor.GetCompiledQuery(Int32 key)
> > System.Xml.Xsl.Processor.StartQuery(XPathNavigator context, Int32 key)
> > System.Xml.Xsl.ForEachAction.Execute(Processor processor, ActionFrame
> > frame)
> > System.Xml.Xsl.ActionFrame.Execute(Processor processor)
> > System.Xml.Xsl.Processor.Execute()
> > System.Xml.Xsl.XslTransform.Transform(XPathNavigator input,
> > XsltArgumentList args, XmlWriter output, XmlResolver resolver)
> > System.Xml.Xsl.XslTransform.Transform(IXPathNavigable input,
> > XsltArgumentList args, XmlWriter output, XmlResolver resolver)
> > com.pop.mm_main_v2.Page_Load(Object sender, EventArgs e) in
> > c:\inetpub\wwwroot\file\index.aspx.cs:61
> > .....
> >
> >
> > When I use XMLSpy to parse the XML using MSXML 4 processor it works perfect.
> > Saxon works perfectly as well. But when I try to parse it trough C#, I get
> > the error above.
> >
> > It looks like I don't use MSXML 4 at all.
> >
> > How do I make sure that MSXML 4 is used when I parse?
> >
> >
> >
> > Thank you,
> >
> > -Mike

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