Reading a XML File, what am I doing wrong?

nuno.silva

Hi,
I need to call a web service and read the XML.
I can call the web service, receive the reply but when I try to read the values, for example put the values on a message, I always get the error “A DotNet variable has not been instantiated. Attempting to call System.Xml.XmlNode.Value in CodeUnit CallWS: GetUsers”



Any sugestion?
thanks in advance,
NS

ftornero

You need to change all reference from XMLNodexx.Value to XMLNodexx.InnerText

And you need to remove the namespaces too.

You can use something like that

RemoveNamespace(XMLDocIn : DotNet "System.Xml.XmlDocument";VAR XMLDocOut : DotNet "System.Xml.XmlDocument")
// before this function your tag looks like this: <namespace:tagname>sample text</tagname>
// after this function your tag looks like this: <tagname>sample text</tagname>
// additionally all namespace references in the head are removed.
XslTransform :=  XslTransform.XslTransform;
XMLStyleSheet := XMLStyleSheet.XmlDocument;
XMLStyleSheet.InnerXml(
'<?xml version="1.0" encoding="UTF-8"?>' +
'<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">' +
'<xsl:output method="xml" encoding="UTF-8" />' +
'<xsl:template match="/">' +
'<xsl:copy>' +
'<xsl:apply-templates />' +
'</xsl:copy>' +
'</xsl:template>' +
'<xsl:template match="*">' +
'<xsl:element name="{local-name()}">' +
'<xsl:apply-templates select="@* | node()" />' +
'</xsl:element>' +
'</xsl:template>' +
'<xsl:template match="@*">' +
'<xsl:attribute name="{local-name()}"><xsl:value-of select="."/></xsl:attribute>' +
'</xsl:template>' +
'<xsl:template match="text() | processing-instruction() | comment()">' +
'<xsl:copy />' +
'</xsl:template>' +
'</xsl:stylesheet>'
);

XslTransform.Load(XMLStyleSheet);
writer := writer.StringWriter();
XslTransform.Transform(XMLDocIn, nullXsltArgumentList, writer);
XMLDocOut := XMLDocOut.XmlDocument;  // Inicializa el XML de salida
XMLDocOut.InnerXml(writer.ToString());

Local vars

Name DataType Subtype Length
XMLStyleSheet DotNet System.Xml.XmlDocument.'System.Xml, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'
XslTransform DotNet System.Xml.Xsl.XslTransform.'System.Xml, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'
writer DotNet System.IO.StringWriter.'mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'
nullXsltArgumentList DotNet System.Xml.Xsl.XsltArgumentList.'System.Xml, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'

And put this code:

RemoveNamespace(XMLResponseDoc, XMLResponseDoc);

before this line:

XMLNodeList := XMLResponseDoc.GetElementsByTagName('Utilizador');

ftornero

Sorry another thing to do is delete the /text() part in SelectSingleNode:

XMLNodeID := XMLNodeContainer.SelectSingleNode('Id');
XMLNodeUserName := XMLNodeContainer.SelectSingleNode('Username');
XMLNodeFullName := XMLNodeContainer.SelectSingleNode('FullName');

HannesHolst

At which line does the debugger stop?

nuno.silva

at the message line

HannesHolst

Maybe this works?

XMLNodeList := XMLResponseDoc.GetElementsByTagName('Utilizador');
FOR I := 0 TO XMLNodeList.Count - 1 DO BEGIN
XMLNodeContainer := XMLNodeList.Item(I);
XMLNodeID := XMLNodeContainer.SelectSingleNode('Id/text()');
XMLNodeUserName := XMLNodeContainer.SelectSingleNode('Username/text()');
XMLNodeFullName := XMLNodeContainer.SelectSingleNode('FullName/text()');

MESSAGE('%1 - %2 - %3', FORMAT(XMLNodeID.Value), FORMAT(XMLNodeUserName.Value), FORMAT(XMLNodeFullName.Value));
END;

nuno.silva

The XMLNodeContainer is the type of System.Xml.XmlNode, correct?
I get the same error.
If I put the code below, ir runs through the records returned by the web service

IF NOT ISNULL(XMLNodeID) THEN
MESSAGE('%1 - %2 - %3', FORMAT(XMLNodeID.Value), FORMAT(XMLNodeUserName.Value), FORMAT(XMLNodeFullName.Value));

ftornero

You need to change all reference from XMLNodexx.Value to XMLNodexx.InnerText

And you need to remove the namespaces too.

You can use something like that

RemoveNamespace(XMLDocIn : DotNet "System.Xml.XmlDocument";VAR XMLDocOut : DotNet "System.Xml.XmlDocument")
// before this function your tag looks like this: <namespace:tagname>sample text</tagname>
// after this function your tag looks like this: <tagname>sample text</tagname>
// additionally all namespace references in the head are removed.
XslTransform :=  XslTransform.XslTransform;
XMLStyleSheet := XMLStyleSheet.XmlDocument;
XMLStyleSheet.InnerXml(
'<?xml version="1.0" encoding="UTF-8"?>' +
'<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">' +
'<xsl:output method="xml" encoding="UTF-8" />' +
'<xsl:template match="/">' +
'<xsl:copy>' +
'<xsl:apply-templates />' +
'</xsl:copy>' +
'</xsl:template>' +
'<xsl:template match="*">' +
'<xsl:element name="{local-name()}">' +
'<xsl:apply-templates select="@* | node()" />' +
'</xsl:element>' +
'</xsl:template>' +
'<xsl:template match="@*">' +
'<xsl:attribute name="{local-name()}"><xsl:value-of select="."/></xsl:attribute>' +
'</xsl:template>' +
'<xsl:template match="text() | processing-instruction() | comment()">' +
'<xsl:copy />' +
'</xsl:template>' +
'</xsl:stylesheet>'
);

XslTransform.Load(XMLStyleSheet);
writer := writer.StringWriter();
XslTransform.Transform(XMLDocIn, nullXsltArgumentList, writer);
XMLDocOut := XMLDocOut.XmlDocument;  // Inicializa el XML de salida
XMLDocOut.InnerXml(writer.ToString());

Local vars

Name DataType Subtype Length
XMLStyleSheet DotNet System.Xml.XmlDocument.'System.Xml, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'
XslTransform DotNet System.Xml.Xsl.XslTransform.'System.Xml, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'
writer DotNet System.IO.StringWriter.'mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'
nullXsltArgumentList DotNet System.Xml.Xsl.XsltArgumentList.'System.Xml, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'

And put this code:

RemoveNamespace(XMLResponseDoc, XMLResponseDoc);

before this line:

XMLNodeList := XMLResponseDoc.GetElementsByTagName('Utilizador');

ftornero

Sorry another thing to do is delete the /text() part in SelectSingleNode:

XMLNodeID := XMLNodeContainer.SelectSingleNode('Id');
XMLNodeUserName := XMLNodeContainer.SelectSingleNode('Username');
XMLNodeFullName := XMLNodeContainer.SelectSingleNode('FullName');

nuno.silva

I already founded a solution below, but I think yours is best, so I replaced my solution by yours.

Thanks @ftornero

  XMLNodeListRead := XMLResponseDoc.GetElementsByTagName('Id');
  XMLNodeID := XMLNodeListRead.Item(I);
  
  XMLNodeListRead := XMLResponseDoc.GetElementsByTagName('Username');
  XMLNodeUserName := XMLNodeListRead.Item(I);
  
  XMLNodeListRead := XMLResponseDoc.GetElementsByTagName('FullName');
  XMLNodeFullName := XMLNodeListRead.Item(I);