Building an XHTML document

var styleInstruction = new XProcessingInstruction (
    "xml-stylesheet", "href='styles.css' type='text/css'"
);

var docType = new XDocumentType ("html",
  "-//W3C//DTD XHTML 1.0 Strict//EN",
  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd", null);

XNamespace ns = "http://www.w3.org/1999/xhtml";
var root =
    new XElement (ns + "html",
        new XElement (ns + "head",
            new XElement (ns + "title", "An XHTML page")),
        new XElement (ns + "body",
            new XElement (ns + "h1", "This is a heading."),
            new XElement (ns + "p", "This is some content."))
    );
    
var doc =
    new XDocument (
        new XDeclaration ("1.0", "utf-8", "no"),
        new XComment ("Reference a stylesheet"),
        styleInstruction,
        docType,
        root
    );

string tempPath = Path.Combine (Path.GetTempPath(), "sample.html");
doc.Save (tempPath);
Process.Start (tempPath);                      // This will display the page in IE or FireFox
File.ReadAllText (tempPath).Dump();

doc.Root.Name.LocalName.Dump ("Root element's local name");

XElement bodyNode = doc.Root.Element (ns + "body");
(bodyNode.Document == doc).Dump ("bodyNode.Document == doc");

(doc.Root.Parent == null).Dump ("doc.Root.Parent is null");

foreach (XNode node in doc.Nodes())
  Console.Write (node.Parent == null);