static void



To debug in Visual Studio 2005, use the XslCompiledTransform(true) constructor.

XslCompiledTransform transformer = new XslCompiledTransform();
XsltArgumentList args = new XsltArgumentList();
args.AddParam("ID", "", "Value"); //second argument is namespace
transformer.Transform("data.xml", args, Response.OutputStream);

Formatted XmlDocument

private static string FormattedXml(XmlNode doc) //quickly format xml string
    MemoryStream ms = new MemoryStream(); //could use stringbuilder but always utf16
    XmlWriterSettings settings = new XmlWriterSettings();
    settings.Indent = true; //in 1.1 an xmlTextwriter with Formatting= Formatting.Indented
    settings.Encoding = Encoding.UTF8;
    using (XmlWriter writer = XmlWriter.Create(ms, settings))
    return Encoding.UTF8.GetString(ms.ToArray());


Everybody writes a version of this when using XmlDocument. Makes it easy to chain together too.

private static XmlElement AddElement(XmlNode parent, string name)
    XmlElement element = parent.OwnerDocument.CreateElement(name);
    return element;

XPath in XDocument

XPath is often more readable for complex parsing. The extension requires "using System.Xml.XPath;"

//using System.Xml.Linq;
var webConfig = XDocument.Load(fileName);
//using System.Xml.XPath;
XElement e = webConfig.XPathSelectElement("configuration/system.web/httpModules/add[@name='AuthModule']");


Doesn't work if the page uses html entities (&nbsp;) and non-closing tags (look out for <script />), but otherwise this is okay.

XmlDocument doc = new XmlDocument();
doc.PreserveWhitespace = true; //if saving
doc.XmlResolver = null; //we don't want to resolve the w3c DTD
XmlNamespaceManager ns = new XmlNamespaceManager(doc.NameTable);
ns.AddNamespace("html", "");

To use entities, create a custom XmlResolver

SQL Server 2005

FOR XML returns Xml Fragments (no root node- append , root('rootName')).
Rename columns with aliases (and tables for xml auto).

2000+ For Xml Raw[('ElementName')] <row NAME="RED"/>
<ElementName NAME="RED"/> with for xml Raw('ElementName')
2000+ For Xml Auto [,Elements] <TABLENAME NAME="RED"/>
NB joined tables are nested
2005+ For Xml Path Easy elements/attributes and nesting- use xpath in alias
select '1' as '@id', 'New York' as 'address/city/@value'
  • Keep together: select '1' as '@id', 'New York' as 'address/city', 'John' as 'name', 'NY' as 'address/state' for xml path has two adddress nodes
  • NULLS: for xml path, elements xsinil to get "null" elements: <CouldbeNull xsi:nil="true" />
  • WITH NAMESPACES('uri' as prefix)

XQuery: For the SQL2005 xml data type, use xmlColumn.query('/xpath') in the sql.
Where xmlColumn.exists('/root/possiblenode')=1
Namespaces: xmlColumn.query(declare namespace a='uri'; /a:element)
Xml contsriuction (with curly braces): xmlColumn.query('<NewRoot> { /OldRoot } </NewRoot>')
There's a for-loop construct
xmlColumn.query('{ for $n in /root/a
return string($n)

There's even xml DML: xmlDolumn.modify('replace value of (/root/a)[1] with "New Text")