Question

I am trying to use XPath in C# to fetch the href value of the <link> nodes at the YouTube most popular Atom feed.

From the documentation I have read online, this process would be relatively simple, something along the lines of:

XmlDocument xml = new XmlDocument();
xml.Load("http://gdata.youtube.com/feeds/api/standardfeeds/most_popular");
XmlNodeList linkNodes;
linkNodes = xml.SelectNodes("/feed/entry/link[@rel='alternate']");

But this doesn’t work, I get no results. I’ve tried adding namespaces with an XmlNamespaceManager but that doesn’t help, either.

Hasty reply would be appreciated! Thank you!

Answer 1

I’m sure adding namespaces properly would help, as I’m sure that’s the problem. Personally I’d use LINQ to XML instead though. Sample code:

using System;
using System.Linq;
using System.Xml.Linq;

public class Test
{
    static void Main()
    {
        string url =
             "http://gdata.youtube.com/feeds/api/standardfeeds/most_popular";
        var doc = XDocument.Load(url);
        XNamespace ns = "http://www.w3.org/2005/Atom";
        var links = doc.Root
                       .Elements(ns + "entry")
                       .Elements(ns + "link")
                       .Where(x => (string) x.Attribute("rel") == "alternate");

        Console.WriteLine(links.Count()); // 25
    }
}