How to select nodes with XPath in C#?

That is a namespace issue; you need to get the name-table, pick an alias, and use that in your query. Or perhaps (in this case) try GetElementsByTagName.

XmlNamespaceManager mgr = new XmlNamespaceManager(xmlDoc.NameTable); mgr.AddNamespace("x", "http://schemas.openxmlformats.org/officeDocument/2006/extended-properties"); foreach (XmlNode node in xmlDoc.SelectNodes("//x:Template", mgr)) { Console.WriteLine("{0}: {1}", node.Name, node.InnerText); } 

Or:

foreach (XmlNode node in xmlDoc.GetElementsByTagName("Template")) { Console.WriteLine("{0}: {1}", node.Name, node.InnerText); } 

Here your xpath expression requires a namespace resolution. you have to instanciate a XmlNamespaceManager and use it in your SelectNodes.

this sample should work

 public static void TestXPath() { string xmlText = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>"; xmlText += "<Properties xmlns=\"http://schemas.openxmlformats.org/officeDocument/2006/extended-properties\" xmlns:vt=\"http://schemas.openxmlformats.org/officeDocument/2006/docPropsVTypes\">"; xmlText += "<Template>Normal</Template> <TotalTime>1</TotalTime> <Pages>1</Pages> <Words>6</Words>"; xmlText += "</Properties>"; XmlDocument xmlDoc = new XmlDocument(); xmlDoc.Load(new System.IO.StringReader(xmlText)); XmlNamespaceManager nsmgr = new XmlNamespaceManager(xmlDoc.NameTable); nsmgr.AddNamespace("res", "http://schemas.openxmlformats.org/officeDocument/2006/extended-properties"); foreach (XmlNode node in xmlDoc.SelectNodes("//res:Template", nsmgr)) { Console.WriteLine("{0}: {1}", node.Name, node.InnerText); } } 

you can also get the default namespace by using and write

string s = xmlDoc.DocumentElement.GetNamespaceOfPrefix(""); nsmgr.AddNamespace("ns", s); 

Why do you need the namespace here anyway? just get rid of these

xmlns=\"http://schemas.openxmlformats.org/officeDocument/2006/extended-properties\" xmlns:vt=\"http://schemas.openxmlformats.org/officeDocument/2006/docPropsVTypes\" 

and your selection will work.