XElement attribute sorting - c#

I have a XML file like that:
<Users>
<User>
<Adress Name="bbbb"/>
<Adress Name="aaaa" />
</User>
</Users>
I want to sort User element's nodes in ascending order. How can I order Adress elements?
Thank you for your help.

If node is your user node:
node.Elements("Adress").OrderBy(e=>e.Attribute("Name").Value)

Are you merely wanting to work with the XML objects in memory or are you looking to store the sorted results back in a file?
This code shows reordering the elements within an XDocument so that you can save it.
string xml = #"<Users>
<User>
<Address Name=""bbbb""/>
<Address Name=""aaaa"" />
</User>
<User>
<Address Name=""dddd""/>
<Address Name=""cccc"" />
</User>
</Users> ";
XDocument document = XDocument.Parse(xml);
var users = document.Root.Elements("User");
foreach (var user in users)
{
var elements = user.Elements("Address").OrderBy(a => a.Attribute("Name").Value).ToArray();
user.Elements().Remove();
user.Add(elements);
}
If you want an ordered in-memory model, then you can do it like this
var query = from user in document.Root.Elements("User")
select new
{
Addresses = from address in user.Elements("Address")
orderby address.Attribute("Name").Value
select new
{
Name = address.Attribute("Name").Value
}
};
foreach (var user in query)
{
foreach (var address in user.Addresses)
{
// do something with address.Name
}
}

Related

How to get enclosure url with XElement C# Console

I read multiple feed from many sources with C# Console, and i have this code where i load XML From sources:
XmlDocument doc = new XmlDocument();
doc.Load(sourceURLX);
XElement xdoc = XElement.Load(sourceURLX);
How to get enclosure url and show as variable?
If I understand your question correctly (I'm making a big assumption here) - you want to select an attribute from the root (or 'enclosing') tag, named 'url'?
You can make use of XPath queries here. Consider the following XML:
<?xml version="1.0" encoding="utf-8"?>
<root url='google.com'>
<inner />
</root>
You could use the following code to retrieve 'google.com':
String query = "/root[1]/#url";
XmlDocument doc = new XmlDocument();
doc.Load(sourceURLX);
String value = doc.SelectSingleNode(query).InnerText;
Further information about XPath syntax can be found here.
Edit: As you stated in your comment, you are working with the following XML:
<item>
<description>
</description>
<enclosure url="blablabla.com/img.jpg" />
</item>
Therefore, you can retrieve the url using the following XPath query:
/item[1]/enclosure[1]/#url
With xml like below
<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0">
<channel>
<title>title</title>
<link>https://www.link.com</link>
<description>description</description>
<item>
<title>RSS</title>
<link>https://www.link.com/xml/xml_rss.asp</link>
<description>description</description>
<enclosure url="https://www.link.com/media/test.wmv"
length="10000"
type="video/wmv"/>
</item>
</channel>
</rss>
You will get url by reading attribute
var document = XDocument.Load(sourceURLX);
var url = document.Root
.Element("channel")
.Element("item")
.Element("enclosure")
.Attribute("url")
.Value;
To get multiple urls
var urls = document.Descendants("item")
.Select(item => item.Element("enclosure").Attribute("url").Value)
.ToList();
Using foreach loop
foreach (var item in document.Descendants("item"))
{
var title = item.Element("title").Value;
var link = item.Element("link").Value;
var description = item.Element("description").Value;
var url = item.Element("enclosure").Attribute("url").Value;
// save values to database
}

Trying to delete an XML Node based on attribute value

I am trying to delete one record from the XML based on some attribute value. My XML structure is given below:
<?xml version="1.0" encoding="utf-8"?>
<Users>
<User>
<UserId>12345</UserId>
<FirstName>abcd</FirstName>
<LastName>efgh</LastName>
<Email>Hello#hello.com</Email>
<IsAdmin>No</IsAdmin>
</User>
<User>
<UserId>67890</UserId>
<FirstName>ijklm</FirstName>
<LastName>nopqr</LastName>
<Email>world#world.com</Email>
<IsAdmin>No</IsAdmin>
</User>
<User>
<UserId>12678</UserId>
<FirstName>stuv</FirstName>
<LastName>wxyz</LastName>
<Email>foo#bar.com</Email>
<IsAdmin>Yes</IsAdmin>
</User>
</Users>
E.g if attribute value is 12345 it should delete the below record from the XML.
<User>
<UserId>12345</UserId>
<FirstName>abcd</FirstName>
<LastName>efgh</LastName>
<Email>Hello#hello.com</Email>
<IsAdmin>No</IsAdmin>
</User>
I tried below code but I am not able to delete anything from the XML.
string path = Server.MapPath("~/XML/users.xml");
XElement xEle = XElement.Load(path);
var qry = from element in xEle.Descendants()
where (string)element.Attribute("UserId").Value == "12345"
select element;
if (qry.Count() > 0)
qry.First().Remove();
xEle.Save(path);
I am unable to figure this out. Any help with be appreciated. Thank you
<UserId>12345</UserId> is a nested sub-element of <User>, not an attribute. See XML attribute vs XML element to see the difference.
Thus you need to do:
var userId = "12345";
var qry = from element in xEle.Descendants("User")
where (string)element.Element("UserId") == userId
select element;
var first = qry.FirstOrDefault();
if (first != null)
first.Remove();
Incidentally, by calling both Count() and First(), you are evaluating your query twice. FirstOrDefault() returns the first matching element, or null if the enumerable is empty, and is thus more efficient.
UserId is not attribute in the XML. Its an element
XElement xEle = XElement.Load("input.xml");
var qry = from element in xEle.Descendants()
where (string)element.Element("UserId") == "12345"
select element;
if (qry.Count() > 0)
qry.First().Remove();
xEle.Save("input.xml");
And in your snippet you are comparing 12345 int with string type

How to count number of XML nodes that contain specific value

I am looking for how to count the nodes in an XML file that contain a value of "No" as well as the total number of elements.
I have the element count working fine, but I am not sure of the logic to look inside the XML for a value to count.
To get the total count I am using:
XmlDocument readDoc = new XmlDocument();
readDoc.Load(MapPath("Results.xml"));
int count = readDoc.SelectNodes("root/User").Count;
lblResults.Text = count.ToString();
Below is my XML:
<?xml version="1.0" encoding="iso-8859-1"?>
<root>
<User>
<URL>http://www.example.com</URL>
<JSEnabled>Yes</JSEnabled>
</User>
<User>
<URL>http://www.example.com</URL>
<JSEnabled>Yes</JSEnabled>
</User>
<User>
<URL>http://www.example.com</URL>
<JSEnabled>Yes</JSEnabled>
</User>
<User>
<URL>http://www.example.com</URL>
<JSEnabled>Yes</JSEnabled>
</User>
<User>
<URL>http://www.example.com</URL>
<JSEnabled>No</JSEnabled>
</User>
XmlDocument readDoc = new XmlDocument();
readDoc.Load(MapPath("Results.xml"));
int count = readDoc.SelectNodes("root/User").Count;
lblResults.Text = count.ToString();
int NoCount = readDoc.SelectNodes("JSEnabled[. = \"No\"]").Count;
Good reference here: http://msdn.microsoft.com/en-us/library/ms256086.aspx
I am looking for how to count the
nodes in an XML file that contain a
value of "No"
In XPath:
count(/root/User[JSEnabled = 'No'])
as well as the total number of
elements.
That you already have it:
count(/root/User)
Or use the expression for selecting the nodes and any DOM method to count Node Set Result members.

how to get root node attribute value using linq

I have the following XML. How to read the root node attribite value and it's decendents using LINQ? I am trying to read "dId" and "dTime" from root node, "id" from Customer element and Order number.
<?xml version="1.0" encoding="utf-8" ?>
<Customers dId="wqwx" dTime="10-9-09 11:23">
<Customer id="1">
<Orders>
<Order number="22" status="ok">
</Orders>
</Customer>
</Customers>
I tried the following code but it doesn't work.
XDocument doc= XDocument.Load(#"C:\Customers.xml");
var q = from c in doc.Descendants("Customers")
select new
{
dID = c.Attribute("dId"),
dTime = c.Attribute("dTime");
}
first, fix your xml (<Order .... />)
then, your linq should look like this....
// .Elements(...) selects all elements of type "Customer"
var q = from c in xDoc.Elements("Customers")
select new
{
dID = c.Attribute("dId"),
dTime = c.Attribute("dTime")
};
you should dl LinqPad... it lets you do Linq queries on the fly, even agains SQL databases. Then, once you get the results you want, copy and past your linq into your source code.
You have to end the order tag with: />
xDoc.Descendants("Customers") should work as well as xDoc.Elements("Customers").
Chris, is there a specific advantage to using .Elements?
You can't use LINQ to access the root tag.
The code below does what you want (I included a well formed xml file as well):
using System;
using System.Linq;
using System.Xml.Linq;
namespace ReadXmlSpike
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Reading file...");
XDocument doc = XDocument.Load("Customers.xml");
var customers =
new
{
DID = (string) doc.Element("Customers").Attribute("did"),
DTime = (DateTime) doc.Element("Customers").Attribute("dTime"),
Customers = from customerxml in doc.Descendants("Customer")
select
new
{
ID = (string)customerxml.Attribute("id"),
Orders = from orderxml in customerxml.Descendants("Order")
select
new
{
Number =(string) orderxml.Attribute("number")
}
}
};
Console.WriteLine("Customersfile with id: {0} and time {1}",customers.DID,customers.DTime);
foreach (var customer in customers.Customers)
{
Console.WriteLine("Customer with id {0} has the following orders:",customer.ID);
foreach (var order in customer.Orders)
{
Console.WriteLine("Order with number {0}",order.Number);
}
}
Console.ReadLine();
}
}
}
and the xml file:
<?xml version="1.0" encoding="utf-8" ?>
<Customers did="www" dTime="10-09-09 11:23">
<Customer id="1">
<Orders>
<Order number="22" status="ok"/>
<Order number="23" status="bad"/>
</Orders>
</Customer>
<Customer id="2">
<Orders>
<Order number="24" status="ok"/>
<Order number="25" status="bad"/>
</Orders>
</Customer>
</Customers>
XDocument d = XDocument.Parse(#"<?xml version='1.0' encoding='utf-8' ?>
<Customers dId='wqwx' dTime='10-9-09 11:23'>
<Customer id='1'>
<Orders>
<Order number='22' status='ok'/>
</Orders>
</Customer>
</Customers>");
var cu = d.Root.Elements().Where(n => n.Name == "Customer");
var c = from cc in cu
select new
{
dId = cc.Document.Root.Attribute("dId").Value,
dTime = cc.Document.Root.Attribute("dTime").Value,
ID = cc.Attribute("id").Value,
number = cc.Element("Orders").Element("Order").Attribute("number").Value
};
foreach (var v in c)
{
Console.WriteLine("dId \t\t= {0}", v.dId);
Console.WriteLine("dTime \t\t= {0}", v.dTime);
Console.WriteLine("CustomerID \t= {0}", v.ID);
Console.WriteLine("OrderCount \t= {0}", v.number);
}
Console Output:
================================
dId = wqwx
dTime = 10-9-09 11:23
CustomerID = 1
OrderCount = 22
请按任意键继续. . .
It does not work the way you wrote it: while printing the above code would complain about anonymous type.
However, with this simple modified version d.Document.Root.Attribute("dId").Value; you can assign it to a string.

LINQ to XML Selecting Child Elements

I am trying to extract information from an XML file into an object using LINQ to XML. Although I can return the document and section Id attributes I cannot get access to the Items for each section element, it returns an IEnumerable of all the items in the document. I know this is correct as I’m calling Descendants but am struggling to get it to return only the child items of each section element. Can anybody help?
XML Document
<root>
<document id="1">
<section id="1.1">
<item id="1.1.1"></item>
<item id="1.1.2"></item>
<item id="1.1.3"></item>
</section>
<section id="1.2">
<item id="1.2.1"></item>
<item id="1.2.2"></item>
</section>
</document>
</root>
LINQ Query
XElement documentRoot = XElement.Load("document.xml");
var documents = (from docs in documentRoot.Descendants("document")
select new
{
Id = (string) docs.Attribute("id"),
Sections = docs.Elements("section"),
Items = docs.Elements("section").Elements("item")
}).ToList();
foreach(var doc in documents)
{
foreach(var section in doc.Sections)
{
Console.WriteLine("SectionId: " + section.Attribute("Id"));
foreach(var item in doc.Items)
{
Console.WriteLine("ItemId: " + section.Attribute("Id"));
}
}
}
You got some small typos, on attribute Id and at item loop. But if you're trying to get all section items into that items collection, you're wrong at design level, as Items should be a Section property, not Document (so you'll need to query your XML twice).
Or, you can to do something like:
var documents =
(from docs in documentRoot.Descendants("document")
select new
{
Id = (string) docs.Attribute("id"),
Sections = docs.Elements("section")
}).ToList();
foreach (var doc in documents)
{
foreach (var section in doc.Sections)
{
Console.WriteLine("SectionId: " + section.Attribute("id"));
foreach (var item in section.Elements("item"))
{
Console.WriteLine("ItemId: " + item.Attribute("id"));
}
}
}
Output:
SectionId: id="1.1"
ItemId: id="1.1.1"
ItemId: id="1.1.2"
ItemId: id="1.1.3"
SectionId: id="1.2"
ItemId: id="1.2.1"
ItemId: id="1.2.2"
Do you want a flat structure ?!?! (from LinqPad)
XElement documentRoot = XElement.Parse (
#"<root>
<document id='1'>
<section id='1.1'>
<item id='1.1.1'></item>
<item id='1.1.2'></item>
<item id='1.1.3'></item>
</section>
<section id='1.2'>
<item id='1.2.1'></item>
<item id='1.2.2'></item>
</section>
</document>
</root>
");
var documents = (from docs in documentRoot.Descendants("section")
select new
{
SectionId = (string) docs.Attribute("id"),
Items = docs.Elements("item")
});
documents.Dump();
This gives 2 SectionId items that containes XElements with related items.

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