I have noticed that XmlWriter.WriteRaw appears to not work properly (it escapes xml characters) when the writer is created using XElement.CreateWriter. The below test case reproduces the problem. Is my usage incorrect? Does anyone know how to achieve the desired behavior? I need to be able to write a raw xml string to an XmlWriter and incorporate that xml into an XElement.
[Test]
public void XElementWriterTest()
{
var xelement = new XElement("test");
using (var writer = xelement.CreateWriter())
{
writer.WriteRaw(#"<some raw='xml' />");
}
Assert.That(xelement.ToString(), Is.EqualTo(#"<test><some raw='xml' /></test>"));
// actual : "<test><some raw='xml' /></test>"
}
Is XElement.Parse() an option for you at all?
[TestMethod]
public void XElementWriterTest()
{
var xelement = new XElement("test");
const string newXML = #"<some raw='xml' />";
var child = XElement.Parse(newXML);
xelement.Add(child);
Assert.AreEqual(xelement.ToString(SaveOptions.DisableFormatting), #"<test><some raw=""xml"" /></test>");
}
Related
I need to change the behaviour of XmlWriter for my project to change the way that empty xml elements are serialised. Currently, my code uses XmlWriter and XmlSerializer like so:
public string Serialize(object o)
{
XmlWriterSettings settings = new XmlWriterSettings();
...
StringWriter stringWriter = new StringWriter();
XmlWriter xmlWriter = XmlWriter.Create(stringWriter, settings);
XmlSerializer serializer = new XmlSerializer(o.GetType());
serializer.Serialize(xmlWriter, o);
return stringWriter.ToString();
}
When serializing my xml, empty elements are being serialized to <emptyElement/>, but I need the xml to serialize empty elements to <emptyElement></emptyElement>. The best solution I've found for this was stated in this a Microsoft forum years ago: https://social.msdn.microsoft.com/Forums/en-US/979315cf-6727-4979-a554-316218ab8b24/xml-serialize-empty-elements?forum=xmlandnetfx
The faster and safer way of doing this is by writing your own subclass of the XmlWriter and give it to XmlSerializer.
YourXmlWriter would aggregate standard one and would translate all WriteEndElement() calls to WriteFullEndElement() calls.
I've tried writing my own subclass of XmlWriter, overriding the two methods I need to override:
public abstract class CustomXmlWriter : XmlWriter
{
public override void WriteEndElement()
{
WriteFullEndElement();
}
public override Task WriteEndElementAsync()
{
return WriteFullEndElementAsync();
}
}
In theory, I believe this should work. However, when trying to use the code, I'm coming up against a brick wall around XmlWriter.Create. I cannot cast the resulting XmlWriter to my CustomXmlWriter for obvious reasons, and I can't override the method as it's a static method.
How am I meant to deal with the static Create method? The only other way I can think of doing this is to scrap the idea of my own CustomXmlWriter, and to simply manipulate the string at the end of my method, but this feels very wrong. I don't know if what I'm trying to achieve is possible, or if there is a simple setting somewhere that I cannot seem to find anywhere.
Try following Regex as a temporary fix. The variable input can be the entire xml string and it will replace every occurrence. :
static void Main(string[] args)
{
string input = "<emptyElement/>";
string patternNullTag = #"\<(?'tagname'\w+)/\>";
string output = Regex.Replace(input, patternNullTag, ReplaceNullElement);
}
static string ReplaceNullElement(Match match)
{
string tagname = match.Value.Replace("<", "").Replace("/>", "");
string newElement = "<" + tagname + ">" + "</" + tagname + ">";
return newElement;
}
This question already has answers here:
Fastest way to add new node to end of an xml?
(10 answers)
Closed 5 years ago.
The standard way to append an XML file in LINQ-to-XML is to read it in, modify the in-memory document, and write the whole file out from scratch. For example:
XDocument doc = XDocument.Load("pathToDoc.xml");
doc.Root.Add(new XElement(namespace + "anotherChild", new XAttribute("child-id", childId)));
doc.Save("pathToDoc.xml");
Or, with a FileStream:
using (FileStream fs = new FileStream("pathToDoc.xml", FileMode.Open, FileAccess.ReadWrite)) {
XDocument doc = XDocument.Load(fs);
doc.Root.Add(new XElement(namespace + "anotherChild", new XAttribute("child-id", childId)));
fs.SetLength(0);
using (var writer = new StreamWriter(fs, new UTF8Encoding(false))) {
doc.Save(writer);
}
}
However, in both cases, the existing XML document is being loaded into memory, modified in memory, and then written from scratch to the XML file. For small XML files this is OK, but for large files with hundreds or thousands of nodes this seems like a very inefficient process. Is there any way to make XDocument (or perhaps something like an XmlWriter) just append the necessary additional nodes to the existing XML document rather than blanking it out and starting from scratch?
This totally depends on the position where you need to add the additional elements. Of course you can implement something that removes the closing "</root>" tag, writes additional elements and then adds the "</root>" again. However, such code is highly optimized for your purpose and you'll probably not find a library for it.
Your code could look like this (quick and dirty, without input checking, assuming that <root/> cannot exist):
using System.IO;
using System.Xml.Linq;
namespace XmlAddElementWithoutLoading
{
class Program
{
static void Main()
{
var rootelement = "root";
var doc = GetDocumentWithNewNodes(rootelement);
var newNodes = GetXmlOfNewNodes(doc);
using (var fs = new FileStream("pathToDoc.xml", FileMode.Open, FileAccess.ReadWrite))
{
using (var writer = new StreamWriter(fs))
{
RemoveClosingRootNode(fs, rootelement);
writer.Write(newNodes);
writer.Write("</"+rootelement+">");
}
}
}
private static void RemoveClosingRootNode(FileStream fs, string rootelement)
{
fs.SetLength(fs.Length - ("</" + rootelement + ">").Length);
fs.Seek(0, SeekOrigin.End);
}
private static string GetXmlOfNewNodes(XDocument doc)
{
var reader = doc.Root.CreateReader();
reader.MoveToContent();
return reader.ReadInnerXml();
}
private static XDocument GetDocumentWithNewNodes(string rootelement)
{
var doc = XDocument.Parse("<" + rootelement + "/>");
var childId = "2";
XNamespace ns = "namespace";
doc.Root.Add(new XElement(ns + "anotherChild", new XAttribute("child-id", childId)));
return doc;
}
}
}
I have a .net Web Api 2 application that delivers data in XML.
My problem:
One of my classes looks like this:
public class Horse
{
public string Name { get;set; }
public string Category { get;set; }
}
When i serialize this, the result is:
<Horse>
<Name>Bobo</Name>
<Category>LargeAnimal</Category>
</Horse>
What i want is to wrap all outgoing XML content with a root element like this:
<Animal>
<Horse>
.....
</Horse>
</Animal>
I was hoping to do this in a custom XmlFormatter. But i can't seem to figure out how to append a root element on the writestream.
What is the best way to resolve this issue?
I have tried tweaking this answer to work in my custom xmlserializer, but doesn't seem to work. How to add a root node to an xml?
( I had a really short amount of time to write this question, so if anything is missing, please leave a comment.)
So.. Tweaked the answer to this question: How to add a root node to an xml? to work with my XmlFormatter.
The following code works, although i feel this is a hackish approach.
public override Task WriteToStreamAsync(Type type, object value, Stream writeStream, HttpContent content, TransportContext transportContext)
{
return Task.Factory.StartNew(() =>
{
XmlSerializer xs = new XmlSerializer(type);
XmlDocument temp = new XmlDocument(); //create a temporary xml document
var navigator = temp.CreateNavigator(); //use its navigator
using (var w = navigator.AppendChild()) //to get an XMLWriter
xs.Serialize(w, value); //serialize your data to it
XmlDocument xdoc = new XmlDocument(); //init the main xml document
//add xml declaration to the top of the new xml document
xdoc.AppendChild(xdoc.CreateXmlDeclaration("1.0", "utf-8", null));
//create the root element
var animal = xdoc.CreateElement("Animal");
animal.InnerXml = temp.InnerXml; //copy the serialized content
xdoc.AppendChild(animal);
using (var xmlWriter = new XmlTextWriter(writeStream, encoding))
{
xdoc.WriteTo(xmlWriter);
}
});
}
I have a object which has a string property that has a value with double quotes in it. I need to serialize this object and then use that XML. I wont be deserializing this xml.
I am having trouble getting the right content in the XML file. Let me explain with a code sample:
[Serializable]
public class Test {
[XmlElement]
public string obj { get; set; }
}
class Program {
static void Main(string[] args) {
var st ="Priority == \"1\"";
Test test = new Test();
test.obj = st;
//Serialize this object
XmlSerializer xsSubmit = new XmlSerializer(typeof(Test));
StringWriter sww = new StringWriter();
XmlWriter writer = XmlWriter.Create(sww, new XmlWriterSettings {
OmitXmlDeclaration = true
});
var ns = new XmlSerializerNamespaces();//just to make things simpler here
ns.Add(string.Empty, string.Empty);
xsSubmit.Serialize(writer, test, ns);
//My XML
var xml = sww.ToString();
}
}
I need my xml to be:
<Test><obj>Priority=="1"</obj></Test>
I now get:
<Test><obj>Priority==\"1\"</obj></Test>
I even tried to encode the string into HTML using var html = HttpUtility.HtmlEncode(st);
In this case, the varible html is in the right format however on serializing I get:
<Test><obj>Priority=="1"</obj></Test>
Need some help please.
There was no issue with the code.
I actually get<Test><obj>Priority=="1"</obj></Test> and this is fine. The mistake I was making was that I was reading the value on the debugger. When I write it somewhere, the content was in the correct format.
The " didnt get converted to " because double quotes are as such accepted in an XML document. I can work with that in this case!
I am trying to write an XML response for my web service however I can't figure out how to make the declaration appear in the response.
My code is like so :
StringBuilder sBuilder = new StringBuilder();
using (XmlWriter writer = XmlWriter.Create(sBuilder))
{
writer.WriteStartDocument();
writer.WriteStartElement("ReportResponse");
Response.WriteXml(writer);
writer.WriteEndElement();
writer.WriteEndDocument();
}
var response = XElement.Parse(sBuilder.ToString());
return response;
Response is just a POCO for storing response data.
I am aware that the Save method includes the declaration and the ToString() method does not. I need to write my declaration back with ToString().
I really just want to return custom XML from my REST Service without casting my string 100 times to return valid XML. Is this even possible or am just spinning my wheels ?
If you want to include xml declaration, you can do it this way:
XDocument xdoc = XDocument.Parse(xmlString);
StringBuilder builder = new StringBuilder();
using (TextWriter writer = new StringWriter(builder))
{
xdoc.Save(writer);
}
Console.WriteLine(builder);
Update:
I've noticed, that StringWriter spoils encoding. So one more option is to do so:
string docWithDeclaration = xdoc.Declaration + xdoc.ToString();