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C# Read a specific element which is in a XML Node

I searched a long time in order to get an answer but as i can see is not working.
I have an XML File and I would like to read a specific element from a node.
For example, this is the XML:
<Root>
<TV>
<ID>2</ID>
<Company>Samsung</Company>
<Series>13523dffvc</Series>
<Dimesions>108</Dimesions>
<Type>LED</Type>
<SmartTV>Yes</SmartTV>
<OS>WebOS</OS>
<Price>1993</Price>
</TV>
</Root>
I want to get the ID element in the code as a variable so i can increment it for the next item which i will add.
This is the code at this moment, but i can not find a way to select something from the item itself.
XDocument doc = XDocument.Load("C:TVList.XML");
XElement TV = doc.Root;
var lastElement = TV.Elements("TV").Last()

A query for the last TV's id (this will return 0 if there are no elements):
var lastId = (int) doc.Descendants("TV")
.Elements("ID")
.LastOrDefault();
You might also want the highest id (in case they're not in order):
var maxId = doc.Descendants("TV")
.Select(x => (int)x.Element("ID"))
.DefaultIfEmpty(0)
.Max();
See this fiddle for a working demo.

Use like this to get id value
XDocument doc = XDocument.Load(#"C:\TVList.XML");
XElement root = doc.Element("Root");
XElement tv = root.Element("TV");
XElement id = tv.Element("ID");
string idvalue = id.Value;
also make your <Type>LED</Tip> tag of xml to <Type>LED</Type> for match

use LINQ on XmlNodeList

<X version="1.0">
<Y id="abc" abv="a"/>
<Y id="edf" abv="e"/>
</X>
I want to select the node whose id is "abc", and return its abv "a".
XmlDocument doc = new XmlDocument();
doc.Load(filePath);
XmlNodeList list = doc.SelectNodes("X/Y");
var node = list.Cast<XmlNode>().Where(node => node["id"].InnerText == "abc")
.Select(x=>x["abv"].InnerText);
But it does't work, node["id"].InnerText is always "". Can you point out where is a problem?
Thanks a lot

Aside from the fact what your code snippet wouldn't be compiled because of non-unique node variable (first outside of linq query and second in "where" method lambda), you have also missed Attributes in your query.
It should be something like
var node = list.Cast<XmlNode>()
.Where(n => n.Attributes["id"].InnerText == "abc")
.Select(x => x.Attributes["abv"].InnerText);

The InnerText for a node is the text that appears between <node> and </node>. So for, eg <Y attributes /> there is no inner text.
You need to use node => node.Attributes["id"].Value == "abc"

Just cast XmlNodeList to List, like that:
List<XmlNode> list = new List<XmlNode>();
foreach(XmlNode a in xmlNodeList)
{
list.Add(a);
}
list.OrderBy((element) => element.ChildNodes[0].InnerText);

C# XML linq query

Hi I have the following XML:
<EPICORTLOG>
<POS>
<ClientId>WkStn.90.1</ClientId>
<Id>POS.90.20140819.251.8279</Id>
<StartTime>2014-08-25T05:12:34</StartTime>
<Store>90</Store>
<SysDate>2014-08-19T00:00:00</SysDate>
<TillNo>1</TillNo>
<Time>2014-08-25T05:12:34</Time>
<Tran>1093</Tran>
<WkStn>1</WkStn>
<WORKSTATION>
<IsAutoLock>1</IsAutoLock>
</WORKSTATION>
<TRADE>
<ITEM>
<Class>102499</Class>
<Desc>NIKE RACER</Desc>
<FinalPrice>82.77</FinalPrice>
<Status>ACTV</Status>
<Style>EV0615</Style>
<Tag>1</Tag>
</ITEM>
</TRADE>
</POS>
</EPICORTLOG>
There are many POS nodes like above in the actual XML. I am trying to fetch the POS node with ID=POS.90.20140819.251.8279 and then the details of Item from that particular node. I have written the following query:
XDocument xdoc = XDocument.Load(XMLFile);
var item = from items in xdoc.Element("EPICORTLOG").Descendants("POS")
where items.Attribute("Id").Value == strSelectedPOSID
select new
{
desc=items.Element("ITEM").Attribute("Desc")
};
But it is not yielding any result for me. Here strSelectedPOSID=POS.90.20140819.251.8279. Please let me know where i am going wrong.

Id and Desc are not an Attributes. they are Elements so you should use
var item = from items in xdoc.Descendants("POS")
where (string)items.Element("Id") == strSelectedPOSID
select new
{
desc = (string)items.Element("ITEM").Element("Desc")
};

I got the value at last!! Following is what i used:
var item = from items in xdoc.Element("EPICORTLOG").Descendants("POS")
where (string)items.Element("Id") == strSelectedPOSID
select new
{
desc = items.Element("TRADE").Element("ITEM").Element("Desc").Value.ToString()
};
Thanks for the inputs.

How do I programmatically determine if an XML node is a leaf node?

I have a big XML tree like the following:
<CategoryArray>
<Category Name="Antiques" ID="20081">
<Category Name="Antiquities" ID="37903">
<Category Name="The Americas" ID="37908" />
<Category Name="Byzantine" ID="162922" />
<Category Name="Celtic" ID="162923" />
<Category Name="Egyptian" ID="37905" />
...
I'd like to iterate through all nodes to populate a control and, when doing so, check to see: is this node a leaft of a parent node? What is the easiest way to do this?

A leaf node is one that has no children so you can simply perform a check if it has children. There are various ways of doing this depending on how you're loading the XML document. For example, you can use the HasChildNodes property.
if (myXmlNode.HasChildNodes)
//is not a leaf
else
//is a leaf

Number of child nodes will give you the answer - 0 child nodes (or only text child node, depending on classes/queries you use) means it is leaf.
I.e. XElement sample form MSDN: Find a List of Child Elements
XDocument cpo = XDocument.Load("PurchaseOrders.xml");
XElement po = cpo.Root.Element("PurchaseOrder").Element("Address");
// list1 contains all children of PurchaseOrder using LINQ to XML query
IEnumerable<XElement> list1 = po.Elements();
// list2 contains all children of PurchaseOrder using XPath expression
IEnumerable<XElement> list2 = po.XPathSelectElements("./*");

I would first flatten the hierarchy - e.g. using the code from this post
How do I select recursive nested entities using LINQ to Entity
And then something like this...
using (XmlReader reader = XmlReader.Create(new StringReader(this.XML)))
{
XElement xml = XElement.Load(reader);
var all = xml.Elements("Category").Flatten(x => x.Elements("Category"));
var leafs = from cat in all
where cat.Elements("Category").Any() == false
select cat;
// or go through all...
var categories =
from cat in all
select new
{
Name = cat.Attribute("Name"),
ID = cat.Attribute("ID"),
IsLeaf = cat.Elements("Category").Any() == false,
SubCount = cat.Elements("Category").Count(),
// Subs = cat.Elements("Category").Select(x => x.Attribute("Name").ToString()).ToArray(),
};
// or put into dictionary etc.
var hash = categories.ToDictionary(x => x.Name);
}

xpath to select elements with last child value

This is my xml file
<profiles>
<profile id='8404'>
<name>john</name>
<name>mark</name>
</profile>
<profile id='8405'>
<name>john</name>
</profile>
</profiles>
and I want to select profiles where last "name" child value= john, the result should contains the profile with id=8405 only
what it the xpath that can evaluate this?
here is my trial:
var filterdFile = profilefileXML.XPathSelectElements("/profiles/profile[name[last()]='john']");
but it doesn't make sense.
Updated:
My trail is correct, there was only a syntax error in it. Thanks all

You can apply multiple indexing operations with successive [...]:
var doc = XDocument.Parse(xml); //the xml from your question
var node = doc.XPathSelectElement("/profiles/profile[name='john'][last()]");
Console.WriteLine(node.Attribute("id").Value); //outputs 8405
This will return the last profile element that contains the element name with a value of john.
If you on the other hand want to return all elements which last name element has a value of john, your XPath should work already:
var nodes = doc.XPathSelectElements("/profiles/profile[name[last()]='john']");
foreach (var node in nodes)
{
Console.WriteLine(node.Attribute("id").Value);
}

You can also try LINQ
XDocument xDoc = XDocument.Load("data.xml");
var matches = xDoc.Descendants("profile")
.Where(profile => XElement.Parse(profile.LastNode.ToString()).Value == "john");
And you can access the xml data with a foreach
foreach(XElement xEle in lastEle)
{
var xAttribute = xEle.Attribute("id");
if (xAttribute != null)
{
var id = xAttribute.Value;
}
var lastName = XElement.Parse(xEle.LastNode.ToString()).Value;
}