Develop Reference

How to get array of subelements from an element?

My xml looks likes this
<stock name="Fish">
<eqn>100</eqn>
<inflow>Spawns</inflow>
<outflow>Deaths</outflow>
<outflow>Flow_1</outflow>
<non_negative/>
</stock>
My code looks likes this
var stockList = from q in variable.Descendants(ns + "stock")
select new {
name = q.FirstAttribute.Value,
initial = q.Element(ns + "eqn").Value,
inflow = q.Element(ns + "inflow").Value,
outflow = q.Element(ns + "outflow").Value
};
This only gives me the first inflow and first outflow, but there are two outflows so I need to be store each one in an array.

You can use the public IEnumerable<XElement> Elements (XName name) method. It returns all the child elements of this element having a matching name.
outflow = q.Elements(ns + "outflow").Select(el => el.Value).ToArray()
or
outflow = (from el in q.Elements(ns + "outflow") select el.Value).ToArray()

simple way to read xml data using linq

I have a xml structure like this. Can anyone help with a simple linq function to read this xml structure.The itemEntry node repeats according to data. I tried to read the xml using the method below,but i am getting no records in the list. Is this method here correct way to get the details...
List<CX_ITEMLIST> sList =
(from e in XDocument.Load(param.FileName).Root.Elements("itemEntry")
select new CX_ITEMLIST
{
TITLE = (string)e.Element("title"),
YEAR = (string)e.Element("year"),
ITEMNAME = (string)e.Element("itemname"),
CATRYLIST =
(
from p in e.Elements("categorylist").Elements("categories")
select new CATLIST
{
IDTYPE = (string)p.Element("categoryid"),
IDNUMBER = (string)p.Element("categoryName")
}).ToList()
}).ToList();
<itemslist>
<itemInformation>
<itemdate>01/23/2014</itemdate>
<itemcount>57</itemcount>
</itemInformation>
<itemEntry>
<title>Title1</title>
<year>2013</title>
<itemname>testname</itemname>
<categorylist>
<categories>
<categoryid>Category1</categoryid>
<categoryName>Category2</categoryName>
</categories>
<categories>
<categoryid>Category1</categoryid>
<categoryName>Category2</categoryName>
</categories>
</categorylist>
</itemEntry>
<itemEntry>
<title>Title1</title>
<year>2013</title>
<itemname>testname</itemname>
<categorylist>
<categories>
<categoryid>Category1</categoryid>
<categoryName>Category2</categoryName>
</categories>
<categories>
<categoryid>Category1</categoryid>
<categoryName>Category2</categoryName>
</categories>
</categorylist>
</itemEntry>
</itemslist>

You should try with XDocument.
XDocument xdoc = XDocument.Load("file.xml");

The System.Xml.XLinq namespace contains some awesome objects to make this easy.
var xDoc = XDocument.Parse(xml); // load your xml string, or use XDocument.Load() to load an xml file
var itemEntries = xDoc
.Root // refers to itemEntries node
.Descendants("itemEntry"); // gets all itemEntry nodes in an IEnumerable object
This gets you an IEnumerable<XNode> of all the itemEntry nodes.
From there you can do what you need, save the values to a business object, etc.

The above method works properly, i found the issue, my xml tag was having namespace attribute. i tried to get the namespace and append it with Elements while reading
XNamespace ns = xDocument.Root.Attribute("xmlns").Value;
List<CX_ITEMLIST> sList =
(from e in XDocument.Load(param.FileName).Root.Elements(ns + "itemEntry")
select new CX_ITEMLIST
{
TITLE = (string)e.Element(ns + "title"),
YEAR = (string)e.Element(ns + "year"),
ITEMNAME = (string)e.Element(ns + "itemname"),
CATRYLIST =
(
from p in e.Elements(ns + "categorylist").Elements(ns + "categories")
select new CATLIST
{
IDTYPE = (string)p.Element(ns + "categoryid"),
IDNUMBER = (string)p.Element(ns + "categoryName")
}).ToList()
}).ToList();

How to get an specific node in xml with namespaces?

I'm dealing to access an specific node from a XML Document. I realized that this one as a base namespace. Here is the example.
I'm interested to get the value of the node d:MediaUrl from all descendents node (entry). And I haven't accomplished that.
When I debug the variable iterator 'i', I can see that the XML includes the default namespace again, something like:
<entry xmlns="http://schemas.microsoft.com.ado/..."
And also I have to include the another namespace called 'd'.
What can I do to access to that particular nodes?
This is what I have.
var doc = XDocument.Parse(result);
string BASE_NS = "http://www.w3.org/2005/Atom";
string d = "http://schemas.microsoft.com/ado/2007/08/dataservices";
var query = from i in doc.Descendants(XName.Get("entry", BASE_NS))
select new Image()
{
Url = i.Element(XName.Get("MediaUrl", BASE_NS)).Value
};
var results = query.ToList();

I would suggest using XNamespace rather than XName (personal preference, mainly - as that's how I've always dealt with namespaces in LINQ to XML). To me it's less effort to set up the namespaces in advance and then use Element(NS + "element name") than to useXName.Get(though usingXName.Get` is perfectly fine if that's what you want to do.
If you want to get a all the "MediaUrl" elements for each entry, then I'd do something like this:
XNamespace d = "http://schemas.microsoft.com/ado/2007/08/dataservices";
var query = (from i in doc.Descendants(d + "MediaUrl")
select new Image()
{
Url = i.Value
}).ToList();
If you want to get only one of them, then you need to do something a little different, depending on which one you wanted to get.
For the properties MediaUrl:
XNamespace d = "http://schemas.microsoft.com/ado/2007/08/dataservices";
XNamespace m = "http://schemas.microsoft.com/ado/2007/08/dataservices/metadata";
var query = (from i in doc.Descendants(m + "properties")
select new Image()
{
Url = i.Element(d + "MediaUrl").Value
}).ToList();
For the Thumbnail MediaUrl:
XNamespace d = "http://schemas.microsoft.com/ado/2007/08/dataservices";
var query = (from i in doc.Descendants(d + "Thumbnail")
select new Image()
{
Url = i.Element(d + "MediaUrl").Value
}).ToList();
The key here is to use the namespace in conjunction with the element name in order to retrieve it.

var query = from i in doc.Descendants("{full namespace for prefix d}MediaUrl")
select new Image()
{
Url = i.Value
};

Sorting XDocument elements based on InnerXML

I have an XML document similar to this:
<document>
<post>
<author>Bill Smith</author>
<subject>Test Article</subject>
<dates>
<uploaded>some date</uploaded>
<published>some date</published>
</dates>
<price>
<provider>Amazon</provider>
<cost>1540</cost>
</price>
<price>
<provider>WH Smith</provider>
<cost>2640</cost>
</price>
</post>
<post>
<author>Bill Smith</author>
<subject>Test Article</subject>
<dates>
<uploaded>some date</uploaded>
<published>some date</published>
</dates>
<price>
<provider>Amazon</provider>
<cost>1540</cost>
</price>
<price>
<provider>WH Smith</provider>
<cost>2640</cost>
</price>
</post>
</document>
I'm using XDocument w/ .NET 4.5. I know there are other methods I could use to sort this.
I have it working OK to pull each post and put it into a Post model. However, I would like to sort the price elements and pick out the lowest price (and also the provider) so I can insert it into my EF database.
Any help would be much appreciated, I'm totally stuck on where to even start with this.

You can give this a try:
XDocument doc = XDocument.Load(#"Data.xml");
var elements = doc.Root
.Elements("post")
.Select(post => new
{
Author = post.Element("author").Value,
Subject = post.Element("subject").Value,
Uploaded = Convert.ToDateTime(post.Element("dates").Element("uploaded").Value),
Published = Convert.ToDateTime(post.Element("dates").Element("published").Value),
Price = new
{
P = post
.Elements("price")
.OrderByDescending(price => Convert.ToDecimal(price.Element("cost").Value))
.Select(o => new
{
Provider = o.Element("provider").Value,
Cost = Convert.ToDecimal(o.Element("cost").Value)
})
.First()
}
});
var p = elements.First();

Based on code you provided, see, if this works:
var xmlDocumentElement = xDocument.Load("xmlData.xml").Root;
var posts = xmlDocumentElement.Elements("post").Select(post => new
{
Author = post.Element("author").Value.ToString(),
Subject = post.Element("subject").Value.ToString(),
AvailableDate = DateTime.Parse(post.Descendants("dates").FirstOrDefault().Value),
Price = GetPriceFromPriceXElement(post.Elements("price").Aggregate((prev, next) =>
Decimal.Parse(prev.Element("cost").Value.ToString()) <= Decimal.Parse(next.Element("cost").Value.ToString()) ? prev : next ))
}
);
public Price GetPriceFromPriceXElement(XElement price)
{
return new Price
{
Provider = price.Element("provider").Value.ToString(),
Cost = price.Element("cost").Value.ToString()
};
}

Try this. It should work. Once you've data, you can massage it. Please take care of NULL etc. This is just basic idea around your requirement.
XDocument doc = XDocument.Load(#"XMLFile1.xml");
var posts = doc.Root.Elements("post")
.Select(p =>
new
{
Author = p.Element("author").Value,
Price = p.Elements("price").OrderBy(a => decimal.Parse(a.Element("cost").Value)).First()
});
foreach(var a in posts)
{
Console.WriteLine(a.Author + " " + a.Price);
}

Here is a pretty straightforward attempt (and actually very similar to Ivan G's answer):
var posts = from post in document.Root.Elements("post")
select new
{
Author = post.Element("author").Value,
Subject = post.Element("subject").Value,
Uploaded = DateTime.Parse(post.Element("dates").Element("uploaded").Value),
Published = DateTime.Parse(post.Element("dates").Element("published").Value),
Price = (from price in post.Elements("price")
let cost = decimal.Parse(price.Element("cost").Value)
orderby cost
select new
{
Provider = price.Element("provider").Value,
Cost = cost
}).First()
};
It works fine for the sample data you gave us (except the dates "some date").
If the data might be incomplete or wrong (i.e. missing/misspelled nodes or wrong datatypes) I would suggest to just take each XElement instead of the values: Author = post.Element("author") etc. Maybe you want to allow posts without an uploaded or published date. This way you can inspect and/or cast/convert data later and maybe fix problems properly.

Stuck on basic Linq to XML query

I'm trying to extract the information from the namecheap sandbox api and can't figure out why my linq queries aren't working.
Here's a sample response.
XML
<ApiResponse Status="OK" xmlns="http://api.namecheap.com/xml.response">
<Errors />
<Warnings />
<RequestedCommand>namecheap.domains.check</RequestedCommand>
<CommandResponse>
<DomainCheckResult Domain="google.com" Available="false" />
</CommandResponse>
<Server>WEB1-SANDBOX1</Server>
<GMTTimeDifference>--4:00</GMTTimeDifference>
<ExecutionTime>0.875</ExecutionTime>
</ApiResponse>
C#
var doc = XDocument.Load(url);
var response = (
from r in doc.Root.Descendants("ApiResponse")
where 1==1
select new {
Errors = r.Element("Errors").Value,
Warnings = r.Element("Warnings").Value,
RequestedCommand = r.Element("RequestedCommand").Value,
CommandResponse = r.Element("CommandResponse").Value,
Server = r.Element("Server").Value
}
);
I've also tried this query with the same doc just to see if a simple example worked.
var test = doc.Descendants("RequestedCommand").First().Value;
But both return null. So where am I going wrong? I'll eventually need to get at the top level elements and the deeper elements within CommandResponse. Any help with that would also be appreciated.
UPDATE
As Jon's answer mentioned, it was mainly an issue with not using the namespace when referencing the various elements. Also used doc.Elements() rather then doc.Root. Descendants().
Here's an updated working version.
XNamespace ns = "http://api.namecheap.com/xml.response";
var response = (
from r in doc.Elements()
select new
{
Errors = r.Element(ns + "Errors").Value,
Warnings = r.Element(ns + "Warnings").Value,
RequestedCommand = r.Element(ns + "RequestedCommand").Value,
CommandResponse = r.Element(ns + "CommandResponse").Value,
Server = r.Element(ns + "Server").Value
}
);

The problem is that you're not using the namespace when you're looking for elements, descendants etc:
XNamespace ns = "http://api.namecheap.com/xml.response";
var doc = XDocument.Load(url);
var response = doc.Root
.Descendants(ns + "ApiResponse")
.Select(r => new {
Errors = r.Element(ns + "Errors").Value,
...
});
(Note that you never need where 1 == 1 in LINQ... I've changed this from query expression syntax as it wasn't giving you anything.)
The namespace is inherited from the <ApiResponse> element as the default namespace for all the other elements, as it's just xmlns=... rather than specifying an alias.
Also note that if you've shown us the whole XML document, then the above won't find any elements, as you're asking for ApiReponse elements below the root element, whereas it is the root element.

I just got Skeeted ;)
Here's something I did in linqpad to get you one of the elements in the XML
var myxml = #"<ApiResponse Status=""OK"" xmlns=""http://api.namecheap.com/xml.response"">
<Server>WEB1-SANDBOX1</Server>
<Errors />
<Warnings />
<RequestedCommand>namecheap.domains.check</RequestedCommand>
<CommandResponse>
<DomainCheckResult Domain=""google.com"" Available=""false"" />
</CommandResponse>
<GMTTimeDifference>--4:00</GMTTimeDifference>
<ExecutionTime>0.875</ExecutionTime>
</ApiResponse>";
//myxml.Dump();
XNamespace p = "http://api.namecheap.com/xml.response";
var doc1 = XElement.Parse(myxml);
var x = from n in doc1.Elements(p + "Server") select n;
x.First().Value.Dump();