C# XPathSelectElement returns null

Question

I am trying to use the XPathSelectElement method of the System.Xml.XPath namespace but for some reason it always returns null, and I have no idea why.

Here is the code:

TextReader stream = new StreamReader("config.ini");
XmlReader reader = XmlReader.Create(stream);
XElement xml = XElement.Load(reader);

XElement file = xml.XPathSelectElement("Config/File");

Here is the XML file it is trying to read:

<?xml version="1.0" encoding="utf-8"?>
<Config>
 <File>serp_feed.xml</File>
</Config>

I have tried many things (adding a namespace table, changing the XPath, etc.) but nothing works!

Any ideas?

Answer 1

Well with XElement.Load the variable named xml is the root element, the "Config" element of the XML sample you posted. And if you use the path Config/File on that element as the context node you are looking for a child element named "Config" having a descendant "File" element. The "Config" element does not have a "Config" child element, it only has a "File" child element. So you want the XPath File or you need XDocument xml = XDocument.Load("config.ini), then your path works.

Answer 2

Try

XElement file = xml.XPathSelectElement("File")

Because you are using XElement.Load rather than XDocument.Load the root will be the element rather that the document, hence the step in the XPath expression is not required.