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xpath to return value from xml doc

I'm wondering if there is a way to do the following with one xpath expression:
I have an XML doc similar to this but with many 'results',
<result>
<id>1</id>
<name>joe</name>
</result>
<result>
<id>2</id>
<name>jim</name>
</result>
I'm passing a variable into a C# utility along with the xml, and want to return the name where the id = the variable.
I could loop through the xml until reach what I'm after but if there's a handy xpath way to do it I'm listening...
thanks

Assuming you have a root element in there like "results" that XPath can validate, and that you don't have any other nodes named "result"...
//result[id=1]/name
Or you could get the text outright, instead of it being returned in a node
//result[id=1]/name/text()
And if you want to make sure that there's only one result, you could surround it with parens and put a [1] after
(//result[id=1]/name/text())[1]
I would also recommend testing with one of the xpath test sites out there like this one, but beware that different xpath/xml parsers sometimes behave differently.

Converting an XML file to a multi-dimensional dictionnary

I'm trying to import XML files into my C# code.
I would like to access these data like a dictionnary element.
Example:
// XML:
<root>
<node>
<value1>
</value1>
<value2>
<properties>
</properties>
</value2>
<randomnode>
<blabla>X</blabla>
</randomnode>
</node>
</root>
// C#:
values["root"]["node"]["randomnode"]["blabla"] == "X" // true
Is there any way to do this?
As far as I've searched, I could only get a dictionnary using XElements, but it was only 2-dimensions and I had to specify names and values as attributes in the XML file.
Thanks for answering!

I suggest you to use dynamic type for this. See here for code. Or here.

I've used sharpSerializer for that. Heres a pretty good walkthrough:
XML Serialization of Generic Dictionary, Multidimensional Array, and Inherited Type, with sharpSerializer .NET

xpath return string instead of nodelist

I am working on a biztalk project and I need to copy (filtered) content from 1 xml to another.
I have to do this with xpath, I can't use xsl transformation.
So my xpath to get the content from the source xml file is this:
//*[not(ancestor-or-self::IN1_Insurance)]|//IN1_Insurance[2]/descendant-or-self::*
Now this returns an xmlNodelist. Is it possible to return a string with all the nodes in it like:
"<root><node>text</node></root>"
If I put string() before my xpath it returns the values, but I want the whole xml in a string (with nodes..), so I could load that string in another xmldocument. I think this is the best method for my problem.
I know I can loop over the xmlnodelist and append the nodes to the new xmldocument, but it's a bit tricky to loop in a biztalk orchestration and I want to avoid this.
The code I can use is C#.
I've tried to just assign the nodelist to the xmldocument, but this throws a cast error (obvious..).
The way I see it is that I have 2 solutions:
assign the nodelist to the xmldocument without a loop (not possible i think in C#)
somehow convert the nodelist to string and load this in the xmldocument
load the xpath directly in the new xmldocument (don't know if this is possible since it returns a nodelist)
Thanks for your help
edit:
sample input:
<root>
<Patient>
<PatientId></PatientId>
<name></name>
</Patient>
<insurance>
<id>1</id>
<billing></billing>
</insurance
<insurance>
<id>2</id>
<billing></billing>
</insurance>
<insurance>
<id>3</id>
<billing></billing>
</insurance>
</root>
Now I want to copy this sample to another xmldocument, but without insurance node 2 and 3 (this is dynamically, so it could be unsurance node 1 and 2 to delete, or 1 and 3...)
So this has to be the output:
<root>
<Patient>
<PatientId></PatientId>
<name></name>
</Patient>
<insurance>
<id>1</id>
<billing></billing>
</insurance>
</root>
What I am doing now is use the xpath to get the nodes I want. Then I want to assign the result to the new xmldocument, but this is not possible since I get the castException
string xpath = "//*[not(ancestor-or-self::IN1_Insurance)]|//IN1_Insurance[2]/descendant-or-self::*";
xmlDoc = new System.Xml.XmlDocument();
xmlDoc = xpath(sourceXml, strXpath); <= cast error (cannot cast xmlnodelist to xmldocuemnt)
I know the syntax is a bit strange, but it is biztalk c# code..

The most straightforward solution would indeed be to "loop over the xmlnodelist and append (import) the nodes to the new xmldocument", but since you can't loop, what other basic things can/can't you do?
To serialize the nodelist, you could try using XmlNodeList.toString(). If that worked, you'd get a strange beast, because it could be duplicating parts of the XML document several times over. Especially since you're explicitly including ancestors and descendants directly in the nodelist. It would not be something that you could parse back in and have a result that resembled the nodelist you started with.
In other words, it would be best to loop over the XmlNodeList and import the nodes to the new XmlDocument.
But even so, I would be really surprised if you wanted to put all these ancestor and descendant nodes:
//*[not(ancestor-or-self::IN1_Insurance)]|//IN1_Insurance[2]/descendant-or-self::
directly into the new XML document. If you post some sample input and the desired output, we can probably help determine if that's the case.
Update:
I see what you're trying to do: copy an XML document, omitting all <insurance> elements (and their descendants) except the one you want.
This can be done without a loop if the output is as simple as your sample output: only one <Patient> and one <insurance> element, with their descendants, under one top-level element.
Something like (I can't test this as I don't have a biztalk server):
string xpathPatient = "/*/Patient";
string xpathInsuran = "/*/insurance[id = " + insId + "]"; // insId is a parameter
xmlDoc = new System.Xml.XmlDocument();
xmlPatient = xpath(sourceXml, xpathPatient);
xmlInsuran = xpath(sourceXml, xpathInsuran);
XmlElement rootNode = xmlDoc.CreateElement("root");
xmlDoc.AppendChild(rootNode);
//**Update: use [0] to get an XmlNode from the returned XmlNodeList (presumably)
rootNode.AppendChild(xmlDoc.ImportNode(xmlPatient[0], true));
rootNode.AppendChild(xmlDoc.ImportNode(xmlInsuran[0], true));
I confess though, I'm curious why you can't use XSLT. You're approaching tasks that would be more easily done in XSLT than in XPath + C# XmlDocument.
Update: since the xpath() function probably returns an XmlNodeList rather than an XmlNode, I added [0] to the first argument to ImportNode() above. Thanks to #Martin Honnen for alerting me to that.

XPath is a query language (only) for XML documents.
It operates on an abstract model -- the XML INFOSET, and cannot either modify the structure of the XML document(s) it operates on or serialize the INFOSET information items back to XML.
Therefore, the only way to achieve such serialization is to use the language that is hosting XPath.
Apart from this, there are obvious problems with yout question, for example these is no element named IN1_Insurance in the provided XML document -- therefore the XPath expression provided:
//*[not(ancestor-or-self::IN1_Insurance)]|//IN1_Insurance[2]/descendant-or-self::*
selects all elements in the document.
Note:
The described task is elementary to fulfil using XSLT.
Finally: If you are allowed to use C# then you can use the XslCompiledTransform (or XslTransform) class. Use its Transform() method to carry out the following transformation against the XML document:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:strip-space elements="*"/>
<xsl:template match="node()|#*">
<xsl:copy>
<xsl:apply-templates select="node()|#*"/>
</xsl:copy>
</xsl:template>
<xsl:template match="insurance[not(id=1)]"/>
</xsl:stylesheet>
This produces exactly the wanted result:
<root>
<Patient>
<PatientId></PatientId>
<name></name>
</Patient>
<insurance>
<id>1</id>
<billing></billing>
</insurance>
</root>

How to embed xml in xml

I need to embed an entire well-formed xml document within another xml document. However, I would rather avoid CDATA (personal distaste) and also I would like to avoid the parser that will receive the whole document from wasting time parsing the embedded xml. The embedded xml could be quite significant, and I would like the code that will receive the whole file to treat the embedded xml as arbitrary data.
The idea that immediately came to mind is to encode the embedded xml in base64, or to zip it. Does this sound ok?
I'm coding in C# by the way.

You could convert the XML to a byte array, then convert it to binary64 format. That will allow you to nest it in an element, and not have to use CDATA.

The W3C-approved way of doing this is XInclude. There is an implementation for .Net at http://mvp-xml.sourceforge.net/xinclude/

Just a quick note, I have gone the base64 route and it works just fine but it does come with a stiff performance penalty, especially under heavy usage. We do this with document fragments upto 20MB and after base64 encoding they can take upwards of 65MB (with tags and data), even with zipping.
However, the bigger issue is that .NET base64 encoding can consume up-to 10x the memory when performing the encoding/decoding and can frequently cause OOM exceptions if done repeatedly and/or done on multiple threads.
Someone, on a similar question recommended ProtoBuf as an option, as well as Fast InfoSet as another option.

Depending on how you construct the XML, one way is to not care about it and let the framework handle it.
XmlDocument doc = new XmlDocument();
doc.LoadXml("<?xml version=\"1.0\" encoding=\"utf-8\" ?><helloworld></helloworld>");
string xml = "<how><are><you reply=\"i am fine\">really</you></are></how>";
doc.GetElementsByTagName("helloworld")[0].InnerText = xml;
The output will be something like a HTMLEncoded string:
<?xml version="1.0" encoding="utf-8"?>
<helloworld><how><are><you
reply="i am fine">really</you></are></how>
</helloworld>

I would encode it in your favorite way (e.g. base64 or HttpServerUtility::UrlEncode, ...) and then embed it.

If you don't need the xml declaration (first line of the document), just insert the root element (with all childs) into the tree of the other xml document as a child of an existing element. Use a different namespace to seperate the inserted elements.

It seems that serialization is the recommended method.

Can't you use XSLT for this? Perhaps using xsl:copy or xsl:copy-of? This is what XSLT is for.

I use Comments for this :
<!-- your xml text -->
[EDITED]
If the embedded xml with comments, replace it with a different syntax.
<?xml version="1.0" encoding="iso-8859-1" ?>
<xml>
<status code="0" msg="" cause="" />
<data>
<order type="07" user="none" attrib="..." >
<xmlembeded >
<!--
<?xml version="1.0" encoding="iso-8859-1" ?>
<xml>
<status ret="000 "/>
<data>
<allxml_here />
<!** embedeb comments **>
</data>
<xml>
-->
</xmlembeded >
</order>
<context sessionid="12345678" scriptname="/from/..." attrib="..." />
</data>
</xml>

What's the quickest (code execution) way to execute an XML reading?

I have to read the XML:
<items>
<item>
<prop1>value1</prop1>
<prop2>value2</prop2>
<prop3>value3</prop3>
</item>
<item>
<prop1>value1</prop1>
<prop2>value2</prop2>
<prop3>value3</prop3>
</item>
</items>
And put the values into a List<CLASS>.
Some options:
Use XMLSerializer to deserialize to a List
Use XMLDocument to read each item using SelectNodes with XPath and put the values into a List
Use XMLReader to read each node and put the values into a List
Other option...

By far the fastest that I have seen is to use XSD.exe to create an XSD and Class to go with it, then use serialization.

Another option would be to use LinqToXml.

If you're in dotnet, install the WCF starter pack. Then you'll have an option "Paste XML as Types", so you can cut the XML you're looking to serialize into the clipboard and paste it into code as a serializable type. Then you can just serialize the XML and get the values through the class.