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Returning all the elements with the specific attribute using XPath

So, I have an XElement within an Xml file that looks something like this:
... More parent nodes
<item cid="0x14c8" name="A" id="0xaf4b6f8">
<item cid="0x57c" luid="2001"/>
<item cid="0x578" luid="2000" value="0"/>
<item cid="0x14fa" name="B">
<item cid="0x57a" luid="2024" value="1.00"/>
<item cid="0x579" luid="2025" value="0"/>
<item link="0xb199640" cid="0x474" luid="5372"/>
...More descendants
</item>
Now, I want to return an IEnumerable<Element> object of the elements that only contain the attribute link using XPath
In my query, I'm doing:
return currentXElement.XPathSelectElements("//item[#link]").Select(item => new Element(item));
But it is returning all the elements from the complete document, not from the currentXElement which is the section that I'm trying to query.
What can I do? I have tried using /item[#link] too, and is not returning anything.
Thanks
EDIT:
At the end, as Sergey suggested,
return currentXElement.Descendants("item").Where(i => i.Attribute("link") != null).Select(item => new IpjItem(item));

//item expression selects item elements no matter where they are in the document. If you want to select items relative to current element, you should use full path. E.g.
xdoc.Root.XPathSelectElements("//item[#name='B']//item[#link]")
Here I assume that //item[#name='B'] selects your currentElement (you should use expression which select your current element), and then with //item[#link] you are searching for descendant items relative to item with name B.
NOTE: I think pure LINQ will be better here
currentXElement.Descendants("item").Where(i => i.Attribute("link") != null)

XPath String that grabs an element with a specific id value

I am trying to create an XPath query/string that grabs a specific element from a XML document. I am attempting to grab the element with the id=38 but my code always returns nothing for some reason.
If you look at my code & the organisation of my XML file can you tell me what XPath I need to grab the element with the id=38?
My code is:
XmlDocument xdoc = new XmlDocument();
xdoc.Load(getProductURL());
XmlNode node = xdoc.DocumentElement.SelectSingleNode("id('38')");
// node always is null for some reason?
The way the xml is organised is like so:
<courseg>
<group isempty="False" isbranch="true" id="1" name="abc">
<group isempty="False" isbranch="true" id="38" name="def"></group>
</group>
</courseg>

The XPath you need is
//*[#id='38']
Here is the example with XDocument:
XDocument xdoc = XDocument.Parse(#"
<courseg>
<group isempty=""False"" isbranch=""true"" id=""1"" name=""abc"">
<group isempty=""False"" isbranch=""true"" id=""38"" name=""def""></group>
</group>
</courseg>");
XElement node = xdoc.Root.XPathSelectElement("//*[#id='38']");
Console.WriteLine(node);

The function id('P38') would select an element with an ID value of P38. But this doesn't just mean "an attribute named 'id'". It means an attribute declared in the DTD or schema as being of type ID. You haven't shown a DTD or schema, and I suspect you don't have one. If you did, and if it declared the id attribute as being of type ID, then your document would be invalid, because an ID value cannot be all-numeric (for legacy SGML reasons, it has to take the form of a name).
In practice the id() function is probably best avoided unless you have severe performance requirements. It's too fragile - it only works when you are validating the source document against a schema or DTD. In XSLT, use key() instead. Alternatively, many processors now recognize the attribute name xml:id as a 'self declaring' ID value without reference to a schema or DTD: use that if your processor supports it.

Use this XPath query:
//*[#id = 38]
It selects every node with id attribute equals to 38. If you have to be more specific, i.e. select group with id attribute equals to 38, use this one:
//group[#id = 38]

When you mention
xdoc.DocumentElement.SelectSingleNode("id('38')"
you are asking xmldocument to search for a child node inside root node whose name is 'id'. But ideally 'id' is an attribute and not a xmlnode.
So you have to use //group[#id = '38'] to get all child node having name 'group' and attribute 'id' with a value of 38

Using xPath in C# to get value of node attribute

If I have the following xml document:
<xml>
<data>
<dataset name="X"></dataset>
</data>
</xml>
How can I use Xpath in c# to retrieve the value of the name attribute (i.e. X)

How can I use Xpath in c# to retrieve the value of the name attribute
(i.e. X)
This XPath expression:
/xml/data/dataset/#name
selects the wanted attribute -- all atributes named name that belong to a dataset element that is a child of a data element that is a child of the top element of the XML document.
However, you want to get the value of the attribute -- not the node itself.
This XPath expression:
string(/xml/data/dataset/#name)
when evaluated, produces the wanted string value.
In C# use the XPathNavigator.Evaluate() method to evaluate the expression above.

Use this XPath:
xml/data/dataset/#name

use this XPath expression:
xml/data/dataset
this will retrieve the dataset node. after that you can use C# tools to retrieve the attribute name from the node.

How to get elements by name in XML using LINQ

I've chosen the title here as my problem is I need to get the Item nodes mentioned in the example.
I have the following XML and am having problems using LINQ to query it, I've been able to parse XML before - however I've been stuck on this for hours and hope someone can help.
Here is my XML data below (example data):
<a:entry
xmlns:a="http://www.w3.org/2005/Atom">
<a:id>98765</a:id>
<info>Data Catalogue</info>
<data>
<items>
<item>
<id>123456</id>
<value>Item One</value>
</item>
<item>
<id>654321</id>
<value>Item Two</value>
</item>
</items>
</data>
<items>
<item>
<id>123456</id>
<value>Item One</value>
</item>
<item>
<id>654321</id>
<value>Item Two</value>
</item>
</items>
<a:author>
<a:name>Catalogue</a:name>
</a:author>
</a:entry>
I want to be able to extract the ID from the Item XML tag under Items, however there is an Items Tag with Item entries under data I DO NOT want these nodes at all - I want root/items/id/id if this were expressed as path. I've tried everything I know with LINQ so if someone could help, things to note although this is sample data it is based on the system - the format cannot be changed so that is not an acceptable solution.
I can't seem to determine where I'm going wrong - every LINQ expression I try returns nothing, I think the namespace is an issue and have tried to integrate this but I'm going in circles.
Solution must work in Silverlight and C#
I have tried the following:
IEnumerable<XElement> nodes =
element.Elements().Where(e => e.Name.LocalName == "items")
However this gets me all the "items" including the ones under "data" I don't want those.
If I do the following on my XML I do see the Names of the Elements displayed:
XElement element = XElement.Parse(data);
foreach (XElement node in element.Elements())
{
MessageBox.Show(node.Name.LocalName);
}
However when I do this I cannot see the node names under items at all - I've checked the XElement and it does have the node and when I output the names above it "items" shows up along with info and id!
foreach (XElement node in element.Elements("items"))
{
MessageBox.Show(node.Name.LocalName);
}

Assuming element is your <a:entry> element:
var ids = element.Element("items")
.Elements("item")
.Select(item => item.Element("id").Value);
The Element and Elements methods return only direct children, not all descendants, so it doesn't return the <items> element which is under <data>

I had a blank Namespace Declaration in my XML I hadn't noticed once I added this into my code it worked - forgot LINQ is very NameSpace oriented!
XNamespace ns = "http://example.org/namespace";
var ids = element.Element(ns + "items")
.Elements("item")
.Select(item => item.Element("id").Value);

trouble parsing deeply nested attributes using LINQ to XML

I have been trying to parse this xml in c#
<schema uri=http://blah.com/schema >
<itemGroups>
<itemGroup description="itemGroup1 label="itemGroup1">
<items>
<item description="The best" itemId="1" label="Nutella"/>
<item description="The worst" itemId="2" label="Vegemite"/>
</items>
</itemGroup>
</itemGroups>
</schema>
\itemGroup1\Nutella-The best
\itemGroup1\Vegemite-The worst
Any help or direction would be appreciated.

XDocument xDoc = XDocument.Load(myXml); //load your XML from file or stream
var rows = xDoc.Descendants("item").Select(x => string.Format(
#"\{0}-{1}\{2}-{3}",
x.Ancestors("itemGroup").First().Attribute("description").Value,
x.Ancestors("itemGroup").First().Attribute("label").Value,
x.Attribute("label").Value,
x.Attribute("description").Value));
Let's break down what we're doing:
xDoc.Descendants("item") gets us all <item> elements in the entire document
Select(x => string.Format(format, args) projects each <item> we got from the last operation into whatever format we specify in the lambda. In this case, a formatted string.
In terms of the XML tree, we're "sitting at" the <item> level, so we need to roll back up the tree to get the data for the parent group using Ancestors. Since that method returns a sequence of elements, we know we want the first (nearest to us) so we can read its attribute.
Now you have an IEnumerable<string>, one for each <item> in your XML document and the information in the format you specified:
foreach(string row in rows)
{
Console.WriteLine(row);
}