Empty namespace using Linq Xml

The “more correct way” would be:

XDocument xdoc = new XDocument(new XDeclaration("1.0", "utf-8", "true"),
new XElement(ns + "urlset",
new XElement(ns + "url",
    new XElement(ns + "loc", "http://www.example.com/page"),
    new XElement(ns + "lastmod", "2008-09-14"))));

Same as your code, but with the “ns +” before every element name that needs to be in the sitemap namespace. It’s smart enough not to put any unnecessary namespace declarations in the resulting XML, so the result is:

<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>http://www.example.com/page</loc>
    <lastmod>2008-09-14</lastmod>
  </url>
</urlset>

which is, if I’m not mistaken, what you want.