Parse Xml response from a get method in C# using Linq

Question

I have following url which returns me XML response in c#: http://www.bnr.ro/files/xml/years/nbrfxrates2017.xml

Now, i want to retrieve the currency in Euro for my date which is present as a paramater in my function. I want to use Linq but i have some problems

My function:

public static void  getXml(String year, String data)
        {
            WebClient webClient = new WebClient();
            string url = "http://www.bnr.ro/files/xml/years/nbrfxrates" + year + ".xml";
            HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;
            HttpWebResponse response = request.GetResponse() as HttpWebResponse;

            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.Load(response.GetResponseStream());
            XElement xe = XElement.Load(response.GetResponseStream());
            var x = (from e in xe.Elements("Cube")
                     where e.Attribute("date").Value.Equals(data)
                     select e.Element("Rate") into p
                     where p.Element("currency").Value.Equals(data)
                     select p.Value);


            Console.WriteLine(x.ToString());


        }

My error is:

The root element is missing on XElement xe = XElement.Load(response.GetResponseStream());

*"but i have some problems"* - your problems can be solved by some solutions — Sergey Berezovskiy, May 11 '17 at 14:28
Why are you creating an `XmlDocument`, loading the response stream in - and then completely forgetting about it? And then trying to create an `XElement` separately? Your error is because you're trying to read the stream again into an element (why?). You don't need both. — Geoff James, May 11 '17 at 14:32

Sergey Berezovskiy · Answer 1 · 2017-05-11T14:44:41.403

1

Method GetResponseStream returns a stream:

Gets the stream that is used to read the body of the response from the server.

You cannot read this stream twice. When you load XmlDocument it reads data from network stream and closes it releasing the connection. When you try to load XElement from the closed stream, you get an error.

You should read response stream only once - e.g. into string or into MemoryStream:

string xml;
using(var reader = new StreamReader(r.GetResponseStream()))
    xml = reader.ReadToEnd();

Note: It's not clear why you need XmlDocument if you are using linq to xml.

edited May 11 '17 at 14:44

answered May 11 '17 at 14:34

Sergey Berezovskiy

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you are right, but my x is not return what i hope so – S.over17 May 11 '17 at 14:38
@S.over17 that is another problem not related to the question. Create new question and provide actual/expected results with problem description – Sergey Berezovskiy May 11 '17 at 14:41
@S.over17 I rolled back the question to original state. See my previous comment – Sergey Berezovskiy May 11 '17 at 16:45

Parse Xml response from a get method in C# using Linq

1 Answers1