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Cant go deeper than root, LINQ to (Funds)XML, C#

I'm working with a specific FundsXML-Schema trying to get all Assetss of a specific XML-File to iterate through.
Short example of xml-file:
<?xml version="1.0" encoding="utf-8"?>
<FundsXML xmlns="http://www.fundsxml.org/XMLSchema/3.0.5" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" Version="3.0.5" xsi:schemaLocation="http://www.fundsxml.org/XMLSchema/3.0.5 FundsXML3.0.5.xsd">
<Date>2015-02-27</Date>
...
<AssetMasterData>
<Asset>
<SecurityCodes>
<ISIN>XXXXXXXXXXXX</ISIN>
</SecurityCodes>
</Asset>
...
<Asset>
</AssetMasterData>
</FundsXML>
I want to iterate through Assets in there. I tried:
XDocument xmlTree = XDocument.Load(xmlPath);
XElement root = xmlTree.Root;
foreach (XElement f in root.Descendants())
{
System.Windows.MessageBox.Show(f.Name.ToString() +" ; "+f.Value.ToString());
}
Output: {http://www.fundsxml.org/XMLSchema/3.0.5}Date ; 2015-02-27
The second part would be to read ISIN of each Asset node.
But I hadn't time to do this, because I'm failing at the first part.
EDIT:
Solution was to search for namespace+name:
foreach (XElement f in root.Descendants("{http://www.fundsxml.org/XMLSchema/3.0.5}Asset"))
Best solution in my opinion:
foreach (XElement f in root.Descendants(xmlTree.Root.GetDefaultNamespace()+"Asset"))

As your XML is in a namespace, you need to add the namespace information to the Descendants query.
You can see an example here
You can try to get the
roots.Descendants()
Without filtering and check the nodes that it returns to confirm this.

Based on the sample data you've provided
<Asset></Asset>
doesn't appear to have any data in it. You would need to get
foreach (XElement f in root.Descendants("ISIN"))
I think anyway. If there's no actual text then you will get a blank or empty value?? So it sounds like it's returning what you're asking for??

Need to add xml element to last parent using linq c#

I'm really new to Linq and C# and I'm stuck on what is probably an obvious problem.
I have an existing XML file
<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<books>
<book>
<title>This is Title 1</title>
<author>John Doe</author>
<categories>
<category>How to</category>
<category>Technical</category>
</book>
<book>
<title>This is Title 2</title>
<author>Jane Brown</author>
<categories>
<category>Fantasy</category>
</categories>
</book>
</books>
I want to add a 2nd category to the second book in this file.
I've gotten this far:
var thiscat = doc.Root
.Element("book")
.Element("categories");
thiscat.Add(new XElement("category", "novel"));
But this adds a 3rd category to the first book. I need to learn how to point 'thiscat' at the last categories element rather than the first one. I've been sniffing around LastNode but haven't managed to get the syntax right.
This is my first question here. Please let me know if I'm not being clear or if I'm doing anything wrong.

Pete,
Here is an example that will search for the book by title This is Title 2 and add another category.
var elem = doc.Root.Elements("book").FirstOrDefault(x => x.Element("title").Value.Equals("This is Title 2"));
if (elem != null)
{
var category = elem.Element("categories");
category.Add(new XElement("category", "novel"));
}
Edit: More explanatoin.
First of we search the documents book elements for the matching title of This is Title 2 (effectively your second entry). By executing the FirstOrDefault extension method we either the get the first matching element (as XElement) or null.
Because we 'could' get a null value we must check if the value is null if not we move into the next step of locating the categories element. This can be done simply calling the elem.Element() method as we only expect one element.
Finally we add a new XElement to the category element.
Hope this helps.
Cheers.

To answer your question quite literally, you could modify the statement as follows:
var thiscat = doc.Root
.Elements("book")
.Skip(1)
.First()
.Element("categories");
The "Element" function returns the first element of that type found. In this case, we used "Elements" instead to return an IEnumerable containing all of the elements named "book", and then we used the LINQ "skip" function to skip the first (returning another IEnumerable of all the remaining elements), and then we took just the first element in the IEnumerable (back to a single XElement).
Another way you could have gotten to the answer is as follows:
var thiscat = doc.Root
.Element("book")
.ElementsAfterSelf()
.First()
.Element("categories");
ElementsAfterSelf returns an IEnumerable of all the sibling elements after the calling object.
LINQ is a really critical part of programming in C# and it's good to see you're trying to learn it from the beginning. Although your methodology here in adding a specific element to a specific place programmatically is questionable (obviously it is a contrived example), in playing around like this you will probably learn a bit about LINQ and that is always good.

First you should get your second book element.According to your code:
var thiscat = doc.Root
.Element("book")
.Element("categories");
This statement returns just one categories element which belongs to your first book.Because you are using Element instead of Elements. Let's go step by step.
A proper way to get second element is using Descendants like this:
var secondBook = doc.Descendants("book")[1];
Descendants returning a collection of your books.And we are getting second element with indexer.Now we need to select your categories element under the book element.
var categories = secondBook.Element("categories");
Now we have our categories element and we can add our new category and save Xml Document:
categories.Add(new XElement("category", "novel"));
doc.Save(path);
And that's all.If you understand that logic you can modify your html file however you like.Besides you can make all of these in one line:
doc.Descendants("book")[1]
.Element("categories")
.Add(new XElement("category", "novel"));

This should work( slightly lengthy solution as it helps understand the fundamentals better):
XmlElement rootNode = xd.DocumentElement; //gives <books> the root node
XmlNodeList cnodes= rootNode.ChildNodes; //gets the childnodes of <books>
XmlNode secondBook= cnodes.Item(1); //second child of <books> i.e., the <book> you want
XmlNodeList bnodes= secondBook.ChildNodes; //gets the childnodes of that <book>
XmlNode categories= bnodes.Item(2); //gets the third child i.e.,<categories>
//making the new <category> node
string xmlContent = "<category>novel</category>";
XmlDocument doc = new XmlDocument();
doc.LoadXml(xmlContent);
XmlNode newNode = doc.DocumentElement;
//making the new node completes
categories.AppendChild(newNode); //append the new node to <categories> as a child

XPathSelectElement select the second when there is more than one

Hi Not sure if this can be done but I know someone here will know :)
using
XElement oNodeEquip = xmlDoc.XPathSelectElement("//ItemAry/Item/Equip");
how would I select Equip from the second in the following:
<TestInfo>
<ItemAry>
<Item>
<testData>ABC</testData>
</Item>
<Item>
<testData>XYZ</testData>
<Equip>xxx</Equip>
</Item>
</ItemAry>
</TestInfo>
there will always be at lease 2 <Item> and the node I want the value from will always be in the second <Item>
this is a WPF app using .Net 4.0

Try this XPath expression:
//ItemAry/Item[2]/Equip
It considers only the second <Item> element.

You can easily do it with Linq to Xml:
XDocument xdoc = XDocument.Load(path_to_xml);
var second = (string)xdoc.Descendants("Item").Skip(1).Element("Equip");

Use:
(/*/ItemAry/Item)[2]/Equip
The currently selected answer can produce unexpected results, depending on the specific XML document at hand:
//ItemAry/Item[2]/Equip
selects the Equip children of all Item elements that are the second Item child of their ItemAry parent.
So, if the source XML document is:
<TestInfo>
<ItemAry>
<Item>
<testData>ABC</testData>
</Item>
<Item>
<testData>XYZ</testData>
<Equip>xxx</Equip>
</Item>
</ItemAry>
<ItemAry>
<Item>
<testData>DEF</testData>
</Item>
<Item>
<testData>TUW</testData>
<Equip>yyy</Equip>
</Item>
</ItemAry>
</TestInfo>
the above potentially-wrong expression selects two elements:
<Equip>xxx</Equip>
<Equip>yyy</Equip>
The correct expression provided in this answer:
(/*/ItemAry/Item)[2]/Equip
selects just:
<Equip>xxx</Equip>

If you are ceratin about position of the node, you can use position() function in your XPath:
XElement oNodeEquip = xmlDoc.XPathSelectElement("//ItemAry/Item[position()=2]/Equip");

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);
}

Read a specific Element Value based on a specific Attribute in Linq?

I'm just learning Linq, and stuck on what I hope is fairly simple. My xml document is like:
<?xml version="1.0" encoding="utf-8"?>
<XDOC>
...
<ItemsDetail>
<Item name="Item1">
<data1>
<Data type="classA">55</Data>
<Data type="classB">66</Data>
</data1>
<data2>
<Data type="classA">77</Data>
<Data type="classB">88</Data>
</data2>
</Item>
</ItemsDetail>
</XDOC>
So I load my XML above into an XDocument type and then query the
var query = from p in ILSXml.Elements("XDOC").Elements("ItemsDetail").Elements("Item")
select p;
Then I run a foreach on on the query.
foreach (var record in query)
{
Console.WriteLine("Name: {0}", record.Attribute("Name").Value);
Console.WriteLine("Data1 ClassA: {0}", record.Element("data1").Element("Data").Attribute("classA").Value);
}
So the line:
Console.WriteLine("Data1 ClassA: {0}", record.Element("data1").Element("Data").Attribute("classA").Value);
does not work which, is what I was pretty much expecting. Do I have to run another series of queries or run some inline anonymous methods?
Oh and please don't comment on the xml, it's not mine, I just have to work with it.

I assume that you're trying to get the value 55? You can use the First method to find the first "Data" element with a "type" attribute value of "classA".
record.Element("data1")
.Elements("Data")
.First(data => data.Attribute("type").Value == "classA")
.Value
Note that the above solution is quite fragile. Any change to the structure of the input xml document is likely to cause a null reference exception.
You can also query XML documents using the more compact XPath query language. XPath has the ability to filter elements using a simple expression wrapped in square brackets. Your code would then look something like this:
foreach (var record in ILSXml.XPathSelectElements("XDOC/ItemsDetail/Item"))
{
Console.WriteLine("Name: {0}",
record.Attribute("name").Value);
Console.WriteLine("Data1 ClassA: {0}",
record.XPathSelectElement("data1/Data[#type='classA']").Value);
}