Develop Reference

How to read a node in a serialized XML file?

I'm trying to read a node in a serialized XML file. Here is the the first part of the XML file (I'm using a screen cap because pasting ended up with weird formatting):
And this is the code I'm using to read the XML and the error it's throwing:
I'm trying to read the <ScenarioDescription> node.
As per request, here's the entire XML file. Unfortunately it's just a complete mess. Here is a link to the XML file.

You should You would need to specify the namespace. In this particular case, the default namespace is used to declare the http://schemas.datacontract.org/2004/07/ModelLib namespace.
var xml = new XmlDocument();
xml.LoadXml(str);
XmlNamespaceManager ns = new XmlNamespaceManager(xml.NameTable);
ns.AddNamespace("x", xml.DocumentElement.NamespaceURI);
var root = xml.DocumentElement;
var test = root.SelectSingleNode("//x:ScenarioDescription",ns);
var scenarioText = test.InnerText;

You can use the following code to access the ScenarioDescription node and its InnerText
var document = new XmlDocument();
document.Load(s);
var root = document.DocumentElement;
var node = root["ScenarioDescription"];
var text = node?.InnerText;
SelectSingleNode accepts the xpath expression, you simply can use XmlElement indexer instead. Otherwise you'll need to create a XmlNamespaceManager instance and add your root namespace to it
You can supply the XmlNamespaceManager object as a parameter to the
SelectNodes or SelectSingleNode method of the XmlDocument class to
execute XPath query expressions that reference namespace-qualified
element and attribute name

Extracting XML Child Elements Where the Parents are in a Defaulted Namespace

I have the below XML and I've been trying to extract the FirstName, LastName and OtherName for a while now I'm running into all sort of problems.
<OmdCds xmlns="cds"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:cdsd="cds_dt"
xsi:schemaLocation="cds ontariomd_cds.xsd">
<PatientRecord>
<Demographics>
<Names>
<cdsd:LegalName namePurpose="L">
<cdsd:FirstName>
<cdsd:Part>SARAH</cdsd:Part>
<cdsd:PartType>GIV</cdsd:PartType>
<cdsd:PartQualifier>BR</cdsd:PartQualifier>
</cdsd:FirstName>
<cdsd:LastName>
<cdsd:Part>GOMEZ</cdsd:Part>
<cdsd:PartType>FAMC</cdsd:PartType>
<cdsd:PartQualifier>BR</cdsd:PartQualifier>
</cdsd:LastName>
<cdsd:OtherName>
<cdsd:Part>GABRIELA</cdsd:Part>
<cdsd:PartType>GIV</cdsd:PartType>
<cdsd:PartQualifier>BR</PartQualifier>
I currently trying to extract with the below c# code but still can't extract the above data. I'm getting a nullreferenceexception.
XmlDocument doc = new XmlDocument();
doc.Load(folder + "\\" + o.ToString());
XmlNamespaceManager namespaceManager = new XmlNamespaceManager(doc.NameTable);
namespaceManager.AddNamespace("cdsd", "http://www.w3.org/2001/XMLSchema-instance");
XmlNode firstName = doc.DocumentElement.SelectSingleNode("/PatientRecord/Demographics/Names/cdsd:LegalName/cdsd:FirstName/cdsd:Part", namespaceManager);
string fName = firstName.InnerText;
MessageBox.Show(fName);
I can see in the local watch item under doc.DocumentElement, all the InnerXML and InnerText. The InnerXML look something like this...
<PatientRecord xmlns=\"cds\"><Demographics><Names><cdsd:LegalName namePurpose=\"L\" xmlns:cdsd=\"cds_dt\"><cdsd:FirstName><cdsd:Part>SARAH</cdsd:Part><cdsd:PartType>GIV</cdsd:PartType><cdsd:PartQualifier>BR</cdsd:PartQualifier></cdsd:FirstName>

You have 3 namespace definitions in the document:
cds - as a default namespace
http://www.w3.org/2001/XMLSchema-instance- with the xsi prefix
cds_dt - with the cdsd prefix
I am wondering that you don't get an error message, because cds and cds_dt are no URIs and namspaces need to be URIs.
If you try to understand an element name you need to replaces the prefix with the actual namespace.
<PatientRecord> reads as {cds}:PatientRecord
<cdsd:LegalName> reads as {cds_dt}:LegalName
Now in XPath 1.0 the same happens with registered namespaces. But XPath does not have a default namespace. So elements without one are not expanded with a default namespace.
You need to register namespace prefixes on the namespace manager. The prefix does not need to be the same as in the document.
namespaceManager.AddNamespace("cdsd", "cds_dt");
namespaceManager.AddNamespace("cds", "cds");
Now you can use the registered namespaces in XPath:
doc.DocumentElement.SelectSingleNode(
"cds:PatientRecord/cds:Demographics/cds:Names/cdsd:LegalName/cdsd:FirstName/cdsd:Part",
namespaceManager
);
If the first character of an XPath expression is a slash the expression is relative to the document, otherwise to the current context node. You call SelectSingleNode() on the doc.DocumentElement - the OmdCds element node. PatientRecord is a child node, so you can start with it or use . for the current context node.

PatientRecord, Demographics and Names are in the cds namespace. This is because of the default namespace declaration on the OmdCds element (xmlns="cds"). The others are in the cdsd namespace, not xsi. You'll have to add them and use them in the XPATH:
namespaceManager.AddNamespace("cdsd", "cdsd");
namespaceManager.AddNamespace("cds", "cds");
XmlNode firstName = doc.DocumentElement.SelectSingleNode(
"/cds:PatientRecord/cds:Demographics/cds:Names/cdsd:LegalName/cdsd:FirstName/cdsd:Part",
namespaceManager);
BTW, you're getting a NullReferenceException because you're making the false assumption that your query will always return a node. You are now seeing what happens when it does not return a node. Always check for null whenever it's possible that a query returns no value.

Instead XmlDocument class you can use Linq to XML, is easy. You need using the System.Xml.Linq namspace, for example:
XDocument xdoc = XDocument.Load("path");
IEnumerable<XElement> nodes = (from p in xdoc.Descendants()
where p.Name.LocalName == "FirstName"
select p).Elements();
foreach (XElement nodeFirstName in nodes)
{
foreach (XElement parts in nodeFirstName.Elements())
{
string strExtracted = parts.Name.LocalName + " " + parts.Value;
}
}
The LocalName property is used beacuse elements have a prefix "cdsd"

C# parsing Xml SelectingNode

I'm having troubles using Xml on my C# program.
the xml http://pastebin.com/Ufxaght6 (from sandbox)
I'm trying to get any info on the XML, I succeed using recursive loop on nodes, but I want to use something more efficient.
I'm trying this :
XmlDocument document = new XmlDocument();
document.LoadXml(response);
XmlNode node = document.SelectSingleNode("/getnewsalesresult/request/user");
if (node != null)
Logger.WriteLine(node.InnerText);
else
Logger.WriteLine("fail");
This gives always a null.
I think the problem comes from the 'getnewsalesresult' (Wildcard maybe ?).
From the XML :
<getnewsalesresult xmlns="http://www.sandbox.priceminister.com/res/schema/getnewsales" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.sandbox.priceminister.com/res/schema/getnewsales http://www.sandbox.priceminister.com/res/schema/getnewsales/getnewsales.2014-02-11.xsd">
Any idea ?
Thanks in advance.

Your XML has default namespace (xmlns="..."). Default namespace has a different nature. The element where the default namespace declared and all of it's descendant without prefix and without different namespace declaration considered in the same default namespace.
The easiest way to get element in namespace is just to ignore the namespace (as also suggested in comment to this question) :
string xpath = "/*[local-name()='getnewsalesresult']/*[local-name()='request']/*[local-name()='user']";
XmlNode node = document.SelectSingleNode(xpath);
A more proper way is to register a prefix that mapped to the default namespace URI, then use that prefix in your XPath :
XmlNamespaceManager ns = new XmlNamespaceManager(new NameTable());
ns.AddNamespace("d", "http://www.sandbox.priceminister.com/res/schema/getnewsales");
XmlNode node =
document.SelectSingleNode("/d:getnewsalesresult/d:request/d:user", ns);
don't miss to pass XmlNamespaceManager object as 2nd parameter of SelectSingleNode().

creating elements with namespace prefix based on multipart xml root declaration

If I do something like this:
System.Xml.XmlDocument xmlDoc = new System.Xml.XmlDocument();
XmlElement e = xmlDoc.CreateElement("ShipmentReceiptNotification");
e.SetAttribute("xmlns", "urn:rosettanet:specification:interchange:ShipmentReceiptNotification:xsd:schema:02.02");
e.SetAttribute("xmlns:ssdh", "urn:rosettanet:specification:domain:Procurement:AccountClassification:xsd:codelist:01.03");
XmlNode ShipmentReceiptNotification0Node = e;
ShipmentReceiptNotification0Node.InnerText = String.Empty;
xmlDoc.AppendChild(ShipmentReceiptNotification0Node);
XmlNode DocumentHeader1Node = xmlDoc.CreateElement("ssdh:DocumentHeader");
ShipmentReceiptNotification0Node.AppendChild(DocumentHeader1Node);
It will result in the prefix of the second node ssdh not to display, only DocumentHeader is displayed. How could I fix this?

You need to create it like this:
XmlNode DocumentHeader1Node = xmlDoc.CreateElement("ssdh", "DocumentHeader", "urn:rosettanet:specification:domain:Procurement:AccountClassification:xsd:codelist:01.03");
The point is XmlDocument needs to know which namespace prefix (first argument) corresponds which namespace URI (third argument). A little bit counter-intuitive, but this is the way it works.
Also note that the line ShipmentReceiptNotification0Node.InnerText = String.Empty; is useless; it's safe to omit it, the element is empty by default.

XmlDocument Remove XMLNS from Root Element

New here, looking to get a little help with my XmlDocument. Is it possible to have string data in my root element AND remove the xmlns= attribute from being shown? I'm looking for something like this:
<Rulebase author=yadda datetime=bingbang version=1.x </Rulebase>
When I try to use my string data by doing:
xmlDom.AppendChild(xmlDom.CreateElement("", "Rulebase", data));
XmlElement xmlRoot = xmlDom.DocumentElement;
It ends up looking like this:
<Rulebase xmlns="version=0 author=username date=7/13/2011 </Rulebase>
and it also appends xmlns="" to all my other nodes.

The CreateElement overload you're using takes a prefix as it's first argument, local name as second, and namespace as third. If you don't want a namespace, don't use this overload. Just use the one that takes a local name as the one and only argument. Then add your data separately as child elements and attributes.
var xmlDom = new XmlDocument();
XmlElement root = xmlDom.CreateElement("Rulebase");
xmlDom.AppendChild(root);
XmlElement data = xmlDom.CreateElement("Data");
root.AppendChild(data);
XmlAttribute attribute = xmlDom.CreateAttribute("author");
attribute.Value = "username";
data.Attributes.Append(attribute);
attribute = xmlDom.CreateAttribute("date");
attribute.Value = XmlConvert.ToString(DateTime.Now, XmlDateTimeSerializationMode.RoundtripKind);
data.Attributes.Append(attribute);
Console.WriteLine(xmlDom.OuterXml);
Creates (formatting added)
<Rulebase>
<Data author="username" date="2011-07-13T22:44:27.5488853-04:00" />
</Rulebase>
Using XmlDocument to generate XML is pretty tedious though. There are many better ways in .NET, like XmlSerializer and DataContractSerializer. You can also use Linq-to-Xml and XElement. Or you can use an XmlWriter.Create(). Lots of options.