using System;

using System.Linq;

using System.Xml;

using System.Xml.Linq;

​

public class Program

{

    public static void Main(string[] args)

    {

        XNamespace ns = "http://www.afd.admin.ch/publicdb/newdb/mwst_kurse";

​

        var doc = XDocument.Load("http://www.afd.admin.ch/publicdb/newdb/mwst_kurse/wechselkurse.php?d=20150701");

​

        var eur = doc.Descendants(ns + "devise")

            .Where(e => (string) e.Attribute("code") == "eur")

            .Select(e => (decimal) e.Element(ns + "kurs"))

            .Single();

​

        Console.WriteLine(eur);

    }

}