LINQ and XmlNodes elements

Question

I am trying to return the the attribute values from this XML, which is a collection of XmlNodes called from a Sharepoint Webmethod.

XML Data

 <Lists xmlns="http://schemas.microsoft.com/sharepoint/soap/">

    <List DocTemplateUrl="" DefaultViewUrl="/Lists/Announcements/AllItems.aspx" MobileDefaultViewUrl="" ID="{E6172717-EB95-4845-B8CB-8161832565C6}" Title="Announcements" Description="Use the Announcements list to post messages on the home page of your site." ImageUrl="/_layouts/images/itann.gif" Name="{E6172717-EB95-4845-B8CB-8161832565C6}" BaseType="0" FeatureId="00bfea71-d1ce-42de-9c63-a44004ce0104" />


    <List DocTemplateUrl="" DefaultViewUrl="/Lists/Calendar/calendar.aspx" MobileDefaultViewUrl="" ID="{C0735477-BE48-4DDF-9D93-3E1F8E993CEC}" Title="Calendar" Description="Use the Calendar list to keep informed of upcoming meetings, deadlines, and other important events." ImageUrl="/_layouts/images/itevent.gif" Name="{C0735477-BE48-4DDF-9D93-3E1F8E993CEC}" BaseType="0" FeatureId="00bfea71-ec85-4903-972d-ebe475780106" />

///... Several more like this
    </Lists>

I have been following a few different guides, just been going through like this one on DiC, and I've managed to get the examples to work.

 public List<Dictionary<string, XmlAttribute>> GetListData(XmlNode collection)
    {            
        #region Test
    string nodeInput = Convert.ToString(collection.OuterXml);

    TextReader sr = new StringReader(nodeInput);

                 //from <List> node, decendant of <Lists>
    var lists = (from list in XElement.Load(sr).Descendants("List")
                 //where the baseType element value equals 0
                 where int.Parse(list.Element("BaseType").Value) == 0
                 //Output the titles values to a list
                 select list.Element("Title").Value).ToList();
     }

    #endregion

I've been trying to adapt a few of the examples to my data to get more of an idea how it works, but this query has not returned any results unlike I expected. I've written besides each line in a comment what I thought the command was doing, could someone illuminate my mistake?

---

Solution

Very easy to find once I knew namespace was the issue.

http://msdn.microsoft.com/en-us/library/bb669152.aspx C# unlike VB requires the namespace even when the nodes aren't prefixed by it.

So I needed an XNamespace

    XNamespace nameSpace = "http://schemas.microsoft.com/sharepoint/soap/";
    XElement node = XElement.Parse(nodeInput);

    var lists = from list in node.Descendants(nameSpace + "List")
                select list;
    foreach (var list in lists)
    {
        var doc = list.Document;
    }

Answer 1

Your code should be

XNamespace ns = "http://schemas.microsoft.com/sharepoint/soap/";

var lists = (from list in XElement.Parse(nodeInput).Descendants(ns + "List")
             where (int)list.Attribute(ns + "BaseType") == 0
             select (string)list.Attribute(ns + "Title")).ToList();