I need to create an XmlDocument partly by using old XML and partly by creating new. The problem is that the old XML contains custom namespaces and I can't seem to be able to use them as I get an XmlException. I've tried to add the namespace to many different places but I can't get over the Exception!
The Exception
System.Xml.XmlException was unhandled by user code
Message='my' is an undeclared prefix. Line 1, position 42.
Source=System.Xml
My Code
XmlDocument doc = new XmlDocument();
XmlSchema schema = new XmlSchema();
schema.Namespaces.Add("my", "http://foobar.com/");
doc.Schemas.Add(schema);
XmlDeclaration dec = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
doc.AppendChild(dec);
XmlElement root = doc.CreateElement("root");
root.SetAttribute("xmlns:my", "http://foobar.com/");
doc.AppendChild(root);
foreach (var item in GetItems())
{
XmlElement elem = doc.CreateElement("item");
elem.SetAttribute("id", item.id);
// Append body to elem
XmlElement body = doc.CreateElement("body");
body.InnerXml = item.Body; // Here is where I get the exception
elem.AppendChild(body);
// Append elem to root
root.AppendChild(elem);
}
Input from Item.Body is similar to
<aaa><bbb my:attr="55">Foo</bbb></aaa>
I expected the output to be similar to
<?xml version="1.0" encoding="utf-8"?>
<root my:attr="http://foobar.com/">
<item id="12345">
<body>
<aaa>
<bbb my:attr="55">Foo</bbb>
</aaa>
</body>
</item>
</root>
I'm open to alternatives to using this method. After I create the XmlDocument I prettyprint it, validate it against a schema and then push it out for the user to see.
The following is a workaround, best I can come up with:
XNamespace my = "http://foobar.com/";
var doc = new XDocument(new XElement("root",
new XAttribute(XNamespace.Xmlns + "my", my)));
var body = new XElement("body");
doc.Root.Add(new XElement("item", new XAttribute("id", 12345), body));
string innerItem = #"<aaa><bbb my:attr=""55"">Foo</bbb></aaa>";
string itemWrap = #"<wrap xmlns:my=""http://foobar.com/"">" + innerItem + "</wrap>";
XElement item = XElement.Parse(itemWrap);
body.Add(item.Element("aaa"));
Console.WriteLine(doc);
Related
Based on this SO solution, adding the same namespace to your child node will prevent creating empty xmlns="" attributes. I'm not getting empty attributes, instead it duplicates the same xmlns in root to child node.
My current output:
<Root xmlns="http://my.namespace">
<FirstElement xmlns="http://my.namespace"/>
</Root>
Expected output:
<Root xmlns="http://my.namespace">
<FirstElement/>
</Root>
Sharing my code:
private XDocument CreateRootTag()
{
XNamespace xmlns = XNamespace.Get("http://my.namespace");
var xdec = new XDeclaration("1.0", "utf-8", "yes");
XDocument xml = new XDocument(
xdec,
new XElement(
xmlns + "Root",
new XAttribute("version", "1.0"),
CreateFirstElementTag())); // <--- adding child node containing duplicate xmlns as root
return xml;
}
private XElement CreateFirstElementTag()
{
XNamespace xmlns = XNamespace.Get("http://my.namespace");
XElement firstElementTag = new XElement(xmlns + "FirstElement","hello");
return firstElementTag;
}
How to prevent persisting xmlns="my.namespace" attributes in child node?
Please let me know if you have any questions.
Thanks.
I ran your code as follows. And didn't encounter any issues.
c#
void Main()
{
XDocument xdoc = CreateRootTag();
Console.WriteLine(xdoc);
}
private XDocument CreateRootTag()
{
XNamespace xmlns = XNamespace.Get("http://my.namespace");
var xdec = new XDeclaration("1.0", "utf-8", "yes");
XDocument xml = new XDocument(
xdec,
new XElement(
xmlns + "Root",
new XAttribute("version", "1.0"),
CreateFirstElementTag())); // <--- adding child node containing duplicate xmlns as root
return xml;
}
private XElement CreateFirstElementTag()
{
XNamespace xmlns = XNamespace.Get("http://my.namespace");
XElement firstElementTag = new XElement(xmlns + "FirstElement", "hello");
return firstElementTag;
}
Output
<Root version="1.0" xmlns="http://my.namespace">
<FirstElement>hello</FirstElement>
</Root>
I have this XML:
<Feedback>
<Officer>Officer</Officer>
<Answers>My text</Answers>
<Date>20190917</Date>
</Feedback>
I want XML to look like this: (Lowercase first letter in main tag)
<feedback>
<Officer>Officer</Officer>
<Answers>My text</Answers>
<Date>20190917</Date>
</feedback>
How to do it using XMLDocument? I can't access this item
If using XmlDocument is not a hard requirement you can do it with linq fairly easily.
You can create a new XML document with the root node named how you want it then loop through the child nodes of the original and add them to your new XML object.
A simple example:
XDocument xDocument = XDocument.Parse("<Feedback><Officer>Officer</Officer><Answers>My text</Answers><Date>20190917</Date></Feedback>");
XDocument newDoc = new XDocument();
XElement rootElement = new XElement("feedback");
newDoc.Add(rootElement);
foreach (var node in xDocument.Root.Elements())
{
newDoc.Root.Add(node);
}
Console.WriteLine(newDoc);
Console.ReadLine();
However here is an example using XmlDocument if you really need to use that:
XmlDocument oldDoc = new XmlDocument();
XmlDocument newXmlDoc = new XmlDocument();
oldDoc.LoadXml("<Feedback><Officer>Officer</Officer><Answers>My text</Answers><Date>20190917</Date></Feedback>");
XmlElement newRoot = newXmlDoc.CreateElement("feedback");
newXmlDoc.AppendChild(newRoot);
XmlNode root = newXmlDoc.DocumentElement;
foreach (XmlNode node in oldDoc.FirstChild.ChildNodes)
{
XmlElement elem = newXmlDoc.CreateElement(node.Name);
elem.InnerText = node.InnerText;
//Add the node to the document.
root.AppendChild(elem);
}
XmlTextWriter writer = new XmlTextWriter(Console.Out);
writer.Formatting = Formatting.Indented;
newXmlDoc.WriteTo(writer);
writer.Flush();
Console.WriteLine();
Console.ReadLine();
In this case, you can change the name directly:
var XML = ""; // Your XML in string
var tempDoc = new XmlDocument();
tempDoc.LoadXml(XML);
tempDoc.InnerXml = tempDoc.InnerXml.Replace("Feedback>", "feedback>");
XML = tempDoc.OuterXml;
This is a simple way to change the name
Do not use in other situations because various errors may arise, e.g another element may end in the same name
I'm trying to write a XML-document programatically.
I need to add <xsd:schema> tag to my document.
Currently I have:
var xmlDoc = new XmlDocument();
var root = xmlDoc.CreateElement("root");
xmlDoc.AppendChild(root);
var xsdSchemaElement = xmlDoc.CreateElement("schema");
xsdSchemaElement.Prefix = "xsd";
xsdSchemaElement.SetAttribute("id", "root");
root.AppendChild(xsdSchemaElement);
However, this renders to:
<root>
<schema id="root" />
</root>
How do I get the tag to be <xsd:schema>?
Already tried var xsdSchemaElement = xmlDoc.CreateElement("xsd:schema"); which simply ignores the xsd:.
Edit #1
Added method
private static XmlSchema GetTheSchema(XmlDocument xmlDoc)
{
var schema = new XmlSchema();
schema.TargetNamespace = "xsd";
return schema;
}
which is called like xmlDoc.Schemas.Add(GetTheSchema(xmlDoc)); but does not generate anything in my target XML.
Using LINQ-to-XML, you can nest XElements and XAttributess in a certain hierarchy to construct an XML document. As for namespace prefix, you can use XNamespace.
Notice that every namespace prefix, such as xsd in your case, has to be declared before it is used, something like xmlns:xsd = "http://www.w3.org/2001/XMLSchema".
XNamespace xsd = "http://www.w3.org/2001/XMLSchema";
var doc =
new XDocument(
//root element
new XElement("root",
//namespace prefix declaration
new XAttribute(XNamespace.Xmlns+"xsd", xsd.ToString()),
//child element xsd:schema
new XElement(xsd + "schema",
//attribute id
new XAttribute("id", "root"))));
Console.WriteLine(doc.ToString());
output :
<root xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<xsd:schema id="root" />
</root>
I have this XML (stored in a C# string called myXML)
<?xml version="1.0" encoding="utf-16"?>
<myDataz xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<listS>
<sog>
<field1>123</field1>
<field2>a</field2>
<field3>b</field3>
</sog>
<sog>
<field1>456</field1>
<field2>c</field2>
<field3>d</field3>
</sog>
</listS>
</myDataz>
and I'd like to browse all <sog> elements. For each of them, I'd like to print the child <field1>.
So this is my code :
XmlDocument xmlDoc = new XmlDocument();
string myXML = "<?xml version=\"1.0\" encoding=\"utf-16\"?><myDataz xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\"><listS><sog><field1>123</field1><field2>a</field2><field3>b</field3></sog><sog><field1>456</field1><field2>c</field2><field3>d</field3></sog></listS></myDataz>"
xmlDoc.Load(myXML);
XmlNodeList parentNode = xmlDoc.GetElementsByTagName("listS");
foreach (XmlNode childrenNode in parentNode)
{
HttpContext.Current.Response.Write(childrenNode.SelectSingleNode("//field1").Value);
}
but seems I can't read a string as XML? I get System.ArgumentException
You should use LoadXml method, not Load:
xmlDoc.LoadXml(myXML);
Load method is trying to load xml from a file and LoadXml from a string. You could also use XPath:
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.LoadXml(xml);
string xpath = "myDataz/listS/sog";
var nodes = xmlDoc.SelectNodes(xpath);
foreach (XmlNode childrenNode in nodes)
{
HttpContext.Current.Response.Write(childrenNode.SelectSingleNode("//field1").Value);
}
Use Linq-XML,
XDocument doc = XDocument.Load(file);
var result = from ele in doc.Descendants("sog")
select new
{
field1 = (string)ele.Element("field1")
};
foreach (var t in result)
{
HttpContext.Current.Response.Write(t.field1);
}
OR : Get the node list of <sog> tag.
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load(myXML);
XmlNodeList parentNode = xmlDoc.GetElementsByTagName("sog");
foreach (XmlNode childrenNode in parentNode)
{
HttpContext.Current.Response.Write(childrenNode.SelectSingleNode("field1").InnerText);
}
The other answers are several years old (and do not work for Windows Phone 8.1) so I figured I'd drop in another option. I used this to parse an RSS response for a Windows Phone app:
XDocument xdoc = new XDocument();
xdoc = XDocument.Parse(xml_string);
Or use the XmlSerializer class.
XmlSerializer xs = new XmlSerializer(objectType);
obj = xs.Deserialize(new StringReader(yourXmlString));
I used the System.Xml.Linq.XElement for the purpose. Just check code below for reading the value of first child node of the xml(not the root node).
string textXml = "<xmlroot><firstchild>value of first child</firstchild>........</xmlroot>";
XElement xmlroot = XElement.Parse(textXml);
string firstNodeContent = ((System.Xml.Linq.XElement)(xmlroot.FirstNode)).Value;
If I want to add, update or delete node in the xml using c#, how can it be done? My xml is shown below. I dont want transactionID node. I want to add a node called <Transformation>XML</Transformation> after corelationID node.
<?xml version="1.0" ?>
<GovTalkMessage xmlns="http://www.govtalk.gov.uk/CM/envelope">
<EnvelopeVersion>2.0</EnvelopeVersion>
<Header>
<MessageDetails>
<Class>HMRC-VAT-DEC</Class>
<Qualifier>poll</Qualifier>
<Function>submit</Function>
<TransactionID />
<CorrelationID>1B93D48C02D740C6B79DE68A27F3ADE5</CorrelationID>
<ResponseEndPoint PollInterval="10">https://secure.dev.gateway.gov.uk/poll</ResponseEndPoint>
<GatewayTimestamp>2011-04-05T07:41:43.018</GatewayTimestamp>
</MessageDetails>
<SenderDetails />
</Header>
<GovTalkDetails>
<Keys />
</GovTalkDetails>
<Body />
</GovTalkMessage>
The easiest thing to use would be LINQ to XML. For example:
XDocument doc = XDocument.Load("file.xml");
XNamespace ns = "http://www.govtalk.gov.uk/CM/envelope";
// Remove TransationID
XElement transactionElement = doc.Descendants(ns + "TransactionID").Single();
transactionElement.Remove();
// Add XML:
XElement correlationElement = doc.Descendants(ns + "CorrelectionID").Single();
XElement newElement = new XElement(ns + "XML");
correlationElement.AddAfterSelf(newElement);
// Save back
doc.Save("new-file.xml");
//Load the XML
XmlDocument documentXML = new XmlDocument();
documentXML.Load(Server.MapPath("AddDeleteUpdate.xml"));
XmlNamespaceManager xmlns = new XmlNamespaceManager(documentXML.NameTable);
xmlns.AddNamespace("bk", "http://www.govtalk.gov.uk/CM/envelope");
//Identify the parent node i.e <MessageDetails>
XmlNode nodeMessage = documentXML.SelectSingleNode("//bk:GovTalkMessage/bk:Header/bk:MessageDetails", xmlns);
//Delete the node.
XmlNode nodeTransactionID = documentXML.SelectSingleNode("//bk:GovTalkMessage/bk:Header/bk:MessageDetails/bk:TransactionID", xmlns);
nodeMessage.RemoveChild(nodeTransactionID);
//Create the new XML noded to be added.
XmlNode controlAttrNode = null;
controlAttrNode = documentXML.CreateElement("Transformation");
controlAttrNode.InnerText = "XML";
controlAttrNode.Attributes.RemoveAll();
//Get the node object to where it need to be added.
XmlNode nodeCorrelation = documentXML.SelectSingleNode("//bk:GovTalkMessage/bk:Header/bk:MessageDetails/bk:CorrelationID", xmlns);
//Insert the node after.
nodeMessage.InsertAfter(controlAttrNode, nodeCorrelation);
documentXML.Save(Server.MapPath("AddDeleteUpdate.xml"));
You'll need
XMLNode.InsertAfter(newChildNode,referenceChildNode)
This should kickstart you:
http://msdn.microsoft.com/en-US/library/system.xml.xmlnode.insertafter%28v=VS.80%29.aspx