Change the default XML xmlns namespace value in .NET - c#

I need to get a list of files from a VS project file. csproj file is XML file, so I use linq to xml to parse it. The problem is in default namespace of csproj file, it is declared like:
xmlns="http://schemas.microsoft.com/developer/msbuild/2003"
Here is the code I use to find "Compile" elements in a csproj file:
XmlReader reader = XmlReader.Create(projectFilePath);
XDocument doc = XDocument.Load(reader);
XmlNameTable nameTable = reader.NameTable;
XmlNamespaceManager nsManager = new XmlNamespaceManager(nameTable);
XNamespace nms = doc.Root.GetDefaultNamespace();
nsManager.AddNamespace("", nms.NamespaceName);
List<XElement> csFiles = new List<XElement>(doc.Root.XPathSelectElements("//Compile", nsManager));
doc.Root.XPathSelectElements returns an empty list.
nsManager.DefaultNamespace has value "http://schemas.microsoft.com/developer/msbuild/2003".
But nsManager.LookupNamespace("xmlns") returns default XML namespace: "http://www.w3.org/2000/xmlns/".
How to change the xmlns namespace value?

Your problem is that you need to be explicit about the namespace with the XPath. It won't just use the default one for the document, you have to name it.
If you change the last two lines to something like this, it will work (I chose the xmlns prefix "default"):
nsManager.AddNamespace("default", nms.NamespaceName);
List<XElement> csFiles = new List<XElement>(doc.Root.XPathSelectElements("//default:Compile", nsManager));
Another option is to use the XContainer methods instead. This way you don't need to worry about using a namespace manager:
XNamespace nms = doc.Root.GetDefaultNamespace();
List<XElement> csFiles = new List<XElement>(doc.Root.Descendants(nms + "Compile"));

Related

Specflow C# - load/edit/save xml file

Im using Visual studio 2019 and I would like to load, edit and save xml file.
xml file:
<?xml version="1.0" encoding="utf-8"?>
<Firstdelivery25 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://www.acm.nl/Operations/2018/09">
<Firstdelivery>
<MessageId xmlns="http://www.acm.nl/DataModel/2018/09">
<Source>ABC</Source>
</MessageId>
</Firstdelivery>
</Firstdelivery25>
Code in Visual studio:
using System.Linq;
using System.Xml.Linq;
using System.Xml;
using TechTalk.SpecFlow;
XDocument xdoc = XDocument.Load(#"C:\\XML files\\25.xml");
var element = xdoc.Elements("Source").FirstOrDefault();
if (element != null)
{
element.Value = "DEF";
}
xdoc.Save(#"C:\\VB_25.xml");
When I execute this, the test is passed successfully.
However, when I open the new created VB_25.xml file, the old value is still there.
Any help/suggestions/tips would be appreciated.
You can try to modifty XML Data by using XPathNavigator.
Here is a simple demo you can refer to.
http://www.acm.nl/DataModel/2018/09 is the xmlns of MessageId.
XmlDocument document = new XmlDocument();
document.Load("test.xml");
XPathNavigator navigator = document.CreateNavigator();
XmlNamespaceManager manager = new XmlNamespaceManager(navigator.NameTable);
manager.AddNamespace("id", "http://www.acm.nl/DataModel/2018/09");
foreach (XPathNavigator nav in navigator.Select("//id:Source", manager))
{
nav.SetValue("Tessssssst");
}
document.Save(#"new.xml");
var element = xdoc.Elements("Source").FirstOrDefault();
Given your provided XML elements will always be null and so you do nothing with your XML and that's why the result looks like the input.
Reason1: Elements() is looking for direct children only and <Source> is not a direct child in your doc.
See https://learn.microsoft.com/en-us/dotnet/api/system.xml.linq.xcontainer.elements?view=net-5.0
Reason2: <Source> tag has a different namespace than the doc itself and so the query is looking in the wrong namespace.
Solution:
XNamespace ns = "http://www.acm.nl/DataModel/2018/09";
var element = xdoc.Descendants(ns + "Source").FirstOrDefault();
See https://learn.microsoft.com/en-us/dotnet/api/system.xml.linq.xcontainer.descendants?view=net-5.0 which is searching for children including their children.
If you expect a node to exist, I'd also recommend to use First() instead of FirstOrDefault(). This way you'll get an exception that would have shown you the reason for your problem.

Get schemalocation in root Node using XmlDocument using c#

i have to fill up an XML file from a DATA TABLE ,my problem is that i have to get the schemaLocation in the root node ,for this i use the code below ,then i have this result,and i dont know where is p1 coming from
In your resulting XML, p1 is a namespace. The code you have posted (in a screenshot) is defining the namespace "xsi", I'm not sure why your result is generating p1 unless you are renaming xsi somewhere that is not shown.
XmlDocument doc = new XmlDocument();
XmlDeclaration declaire = doc.CreateXmlDeclaration("1.0", "utf-8", null);
XmlElement rootnode = doc.CreateElement("BMECAT");
doc.InsertBefore(declaire, doc.DocumentElement);
doc.AppendChild(rootnode);
rootnode.SetAttribute("version", "2005");
XmlAttribute atr = doc.CreateAttribute("xsi", "schemaLocation", "http://www.w3.org/2001/XMLSchema-instance");
atr.Value = "http://www.adlnet.org/xsd/adlcp.vlp3";
rootnode.SetAttributeNode(atr);
rootnode.Attributes.Append(atr);
In your code:
XmlAttribute atr = doc.CreateAttribute("xsi", "schemaLocation", "http://www.w3.org/2001/XMLSchema-instance");
"xsi" is the name of the namespace it generates, you can control it there. This results in:
<?xml version="1.0" encoding="utf-8"?>
<BMECAT version="2005" xsi:schemaLocation="http://www.adlnet.org/xsd/adlcp.vlp3" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" />
I'm not sure your code matches the result file you provided. When I ran the code, I get "xsi" as expected. If I set "xsi" to null there, it uses a default name, which in my case was d1p1. All instances of "xsi" were replaced with "d1p1". This makes me believe that code might be slightly different from what generated your result. I don't know where "d1p1" came from, it's likely a generated default namespace. This seems like a common default (Remove "d1p1" namespace prefix in DataContractSerializer XML output). In your provided code, if you change "xsi" to "p1" you would get your result.
I might suggest using this method instead:
How to Add schemaLocation attribute to an XML document
Here you would use the accepted answer against your XmlElement rootnode.
XmlElement.SetAttributeValue (localname, prefix, namespace, value)
Please try this code and let me know whether this helped you or not.
Particularly in this code i parse XML file and get the root element:
Then use it to select all attributes named schemaLocation. There is only one, so you can use SelectSingleNode:
The variable
schemaLocationAttribute
Contanins Value attribute through which you can get actual value.
XmlReader xmlReader = XmlReader.Create("MyXML.xml");
XmlDocument xmlDocument = new XmlDocument();
xmlDocument.Load(xmlReader);
XmlElement root = xmlDocument.DocumentElement;
XmlNode schemaLocationAttribute = root.SelectSingleNode("//#*[local-name()='schemaLocation']");
//Single schema value
string schemaValue = schemaLocationAttribute.Value;
//If you have multiple values in your schema
//you have to store it inside of array
string[] multipleShcemavalues = schemaLocationAttribute.Value.Split(null);
//And you have to choose whuickelement you want to use
string chooosendShcema = multipleShcemavalues[1]; //For example

Get nodes from xml files

How to parse the xml file?
<?xml version="1.0" encoding="UTF-8"?>
<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
<sitemap>
<loc>link</loc>
<lastmod>2011-08-17T08:23:17+00:00</lastmod>
</sitemap>
<sitemap>
<loc>link</loc>
<lastmod>2011-08-18T08:23:17+00:00</lastmod>
</sitemap>
</sitemapindex>
I am new to XML, I tried this, but it seems to be not working :
XmlDocument xml = new XmlDocument(); //* create an xml document object.
xml.Load("sitemap.xml");
XmlNodeList xnList = xml.SelectNodes("/sitemapindex/sitemap");
foreach (XmlNode xn in xnList)
{
String loc= xn["loc"].InnerText;
String lastmod= xn["lastmod"].InnerText;
}
The problem is that the sitemapindex element defines a default namespace. You need to specify the namespace when you select the nodes, otherwise it will not find them. For instance:
XmlDocument xml = new XmlDocument();
xml.Load("sitemap.xml");
XmlNamespaceManager manager = new XmlNamespaceManager(xml.NameTable);
manager.AddNamespace("s", "http://www.sitemaps.org/schemas/sitemap/0.9");
XmlNodeList xnList = xml.SelectNodes("/s:sitemapindex/s:sitemap", manager);
Normally speaking, when using the XmlNameSpaceManager, you could leave the prefix as an empty string to specify that you want that namespace to be the default namespace. So you would think you'd be able to do something like this:
// WON'T WORK
XmlDocument xml = new XmlDocument();
xml.Load("sitemap.xml");
XmlNamespaceManager manager = new XmlNamespaceManager(xml.NameTable);
manager.AddNamespace("", "http://www.sitemaps.org/schemas/sitemap/0.9"); //Empty prefix
XmlNodeList xnList = xml.SelectNodes("/sitemapindex/sitemap", manager); //No prefixes in XPath
However, if you try that code, you'll find that it won't find any matching nodes. The reason for this is that in XPath 1.0 (which is what XmlDocument implements), when no namespace is provided, it always uses the null namespace, not the default namespace. So, it doesn't matter if you specify a default namespace in the XmlNamespaceManager, it's not going to be used by XPath, anyway. To quote the relevant paragraph from the Official XPath Specification:
A QName in the node test is expanded into an expanded-name using the
namespace declarations from the expression context. This is the same
way expansion is done for element type names in start and end-tags
except that the default namespace declared with xmlns is not used: if
the QName does not have a prefix, then the namespace URI is null (this
is the same way attribute names are expanded). It is an error if the
QName has a prefix for which there is no namespace declaration in the
expression context.
Therefore, when the elements you are reading belong to a namespace, you can't avoid putting the namespace prefix in your XPath statements. However, if you don't want to bother putting the namespace URI in your code, you can just use the XmlDocument object to return the URI of the root element, which in this case, is what you want. For instance:
XmlDocument xml = new XmlDocument();
xml.Load("sitemap.xml");
XmlNamespaceManager manager = new XmlNamespaceManager(xml.NameTable);
manager.AddNamespace("s", xml.DocumentElement.NamespaceURI); //Using xml's properties instead of hard-coded URI
XmlNodeList xnList = xml.SelectNodes("/s:sitemapindex/s:sitemap", manager);
Sitemap has 2 sub nodes "loc" and "lastmod". The nodes that you are accessing are "name" and "url". that is why you are not getting any result. Also in your XML file the last sitemap tag is not closed properly with a corresponding Kindly try xn["loc"].InnerText and see if you get the desired result.
I would definitely use LINQ to XML instead of the older XmlDocument based XML API. You can accomplish what you are looking to do using the following code. Notice, I changed the name of the element that I am trying to get the value of to 'loc' and 'lastmod', because this is what is in your sample XML ('name' and 'url' did not exist):
XElement element = XElement.Parse(XMLFILE);
IEnumerable<XElement> list = element.Elements("sitemap");
foreach (XElement e in list)
{
String LOC= e.Element("loc").Value;
String LASTMOD = e.Element("lastmod").Value;
}

Parsing complex XML with C#

I am trying to parse a complex XML with C#, I am using Linq to do it. Basically, I am doing a request to a server and I get XML, this is the code:
XElement xdoc = XElement.Parse(e.Result);
this.newsList.ItemsSource =
from item in xdoc.Descendants("item")
select new ArticlesItem
{
//Image = item.Element("image").Element("url").Value,
Title = item.Element("title").Value,
Description = this.Strip(item.Element("description").Value).Substring(0, 200).ToString()
}
And this is the XML structure:
<item>
<test:link_id>1282570</test:link_id>
<test:user>SLAYERTANIC</test:user>
<title>aaa</title>
<description>aaa</description>
</item>
How I can access to the property test:link_id for example?
Thanks!
Currently your XML is invalid since the test namespace is not declared, you can declare it like this:
<item xmlns:test="http://foo.bar">
<test:link_id>1282570</test:link_id>
<test:user>SLAYERTANIC</test:user>
<title>aaa</title>
<description>aaa</description>
</item>
Having this you can use XNamespace to qualify the XML element you want with the correct namespace:
XElement xdoc = XElement.Parse(e.Result);
XNamespace test = "http://foo.bar";
this.newsList.ItemsSource = from item in xdoc.Descendants("item")
select new ArticlesItem
{
LinkID = item.Element(test + "link_id").Value,
Title = item.Element("title").Value,
Description = this.Strip(item.Element("description").Value).Substring(0, 200).ToString()
}
To write a query on XML that is in a
namespace, you must use XName objects
that have the correct namespace. For
C#, the most common approach is to
initialize an XNamespace using a
string that contains the URI, then use
the addition operator overload to
combine the namespace with the local
name.
To retrieve the value of the link_id element you will need to declare and use an XML namespace for the test:link element.
Since you did not show the namespace declaration in your example XML, I am going to assume it is declared somewhere elese in the XML document. You need to locate the namespace declaration in the XML ( something like xmlns:test="http://schema.example.org" ) which is often declared in the root of the XML document.
After you know this, you can do the following to retrieve the value of the link_id element:
XElement xdoc = XElement.Parse(e.Result);
XNamespace testNamespace = "http://schema.example.org";
this.newsList.ItemsSource = from item in xdoc.Descendants("item")
select new ArticlesItem
{
Title = item.Element("title").Value,
Link = item.Element(testNamespace + "link_id").Value,
Description = this.Strip(item.Element("description").Value).Substring(0, 200).ToString()
}
See the XNamespace and Namespaces in C#, and How to: Write Queries on XML in Namespaces for further information.

Reading XML with XDocument problem

I have a following XML (part of a .rdl report):
<Report xmlns:rd="http://schemas.microsoft.com/SQLServer/reporting/reportdesigner" xmlns="http://schemas.microsoft.com/sqlserver/reporting/2008/01/reportdefinition">
<DataSources>
<DataSource Name="TMSSharepointDataSource">
<DataSourceReference>TMSSharepointDataSource</DataSourceReference>
<rd:DataSourceID>f06ffa33-238f-4d83-adfe-1eaa8df96e90</rd:DataSourceID>
</DataSource>
</DataSources>
</Report>
I try to parse and read it using following code:
byte[] fileContent = File.ReadAllBytes(#"path");
UTF8Encoding unicode = new UTF8Encoding();
string stringContent = unicode.GetString(fileContent);
XDocument xml = XDocument.Parse(stringContent);
XElement dsNode = xml.Root.Element("DataSources");
I can't figure out why is dsNode always null?
It's a namespace issue... you need to specify the namespace for the DataSources element. Fortunately, LINQ to XML makes this really easy:
XNamespace ns = "http://schemas.microsoft.com/sqlserver/" +
"reporting/2008/01/reportdefinition";
XElement dsNode = xml.Root.Element(ns + "DataSources");
Note the xmlns="http://..." part of the root element, which means that element and all elements below it which don't have an explicit namespace inherit that namespace.
You are probably missing a namespace reference. Your DataSources will inherit the namespace of the Report node and you will need both the namespace and element local name to generate an XName.
Alternatively you can do the following and skip the namespace check:
XElement dsNode =
xml
.Root
.DescendantNodes()
.Where(e => e.Name.LocalName.Equals("DataSources"))
.First();
This will return the first node where the local name is DataSources. In your example this will be the DataSources element.
Also, your loading of the document is very clumsy. I would suggest the following instead:
XDocument xml = XDocument.Load(File.OpenRead(#"path"));

Categories