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XML Deserialization encoding issue

I already searched a lot and unable to find a solution and unable to determine the correct approach
I am serializing an object to xml string and deserializing it back to an object using c#. XML string after serialization adds a leading ?. When I dezerialize it back to the object I am getting an error There is an error in XML document (1, 1)
?<?xml version="1.0" encoding="utf-16"?>
Serialization code:
string xmlString = null;
MemoryStream memoryStream = new MemoryStream();
XmlSerializer xs = new XmlSerializer(typeof(T));
XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
ns.Add("abc", "http://example.com/abc/");
XmlTextWriter xmlTextWriter = new XmlTextWriter(memoryStream,Encoding.Unicode);
xs.Serialize(xmlTextWriter, obj, ns);
memoryStream = (MemoryStream)xmlTextWriter.BaseStream;
xmlString = ConvertByteArrayToString(memoryStream.ToArray());
ConvertByteArrayToString:
UnicodeEncoding encoding = new UnicodeEncoding();
string constructedString = encoding.GetString(characters);
Deserialization Code:
XmlSerializer ser = new XmlSerializer(typeof(T));
StringReader stringReader = new StringReader(xml);
XmlTextReader xmlReader = new XmlTextReader(stringReader);
object obj = ser.Deserialize(xmlReader);
xmlReader.Close();
stringReader.Close();
return (T)obj;
I would like to know what I am doing wrong with encoding and I need a solution that works for most cases. Thanks

Use following function for serialization and Deserialization
public static string Serialize<T>(T dataToSerialize)
{
try
{
var stringwriter = new System.IO.StringWriter();
var serializer = new XmlSerializer(typeof(T));
serializer.Serialize(stringwriter, dataToSerialize);
return stringwriter.ToString();
}
catch
{
throw;
}
}
public static T Deserialize<T>(string xmlText)
{
try
{
var stringReader = new System.IO.StringReader(xmlText);
var serializer = new XmlSerializer(typeof(T));
return (T)serializer.Deserialize(stringReader);
}
catch
{
throw;
}
}

Your serialized XML contains a Unicode byte-order mark in the beginning, and this is where the deserializer fails.
To remove the BOM you need to create a different version of encoding suppressing BOM instead of using default Encoding.Unicode:
new XmlTextWriter(memoryStream, new UnicodeEncoding(false, false))
Here the second false prevents BOM being prepended to the string.

Writing an XML fragment using XmlWriterSettings and XmlSerializer is giving an extra character

I need to write an XML fragment to be consumed by a web service. Any xml declarations cause the web service to reject the request. To support this I have the following class:
public class ContentQueryCriteria
{
public int Type { get; set; }
public string Value { get; set; }
public int Condition { get; set; }
}
which allow me to set the request criteria and then get the results.
The code is used like this:
ContentQueryCriteria content = new ContentQueryCriteria();
content.Type = 1;
content.Value = "NAVS500";
content.Condition = 1;
string requestBody = SerializeToString(content);
Console.WriteLine(requestBody);
When I serialize this to an XML file I get a proper response, without the XML declaration or any namespaces. However, I would rather capture the data in a memory stream rather then a file.
Using the following method (taken from http://www.codeproject.com/Articles/58287/XML-Serialization-Tips-Tricks ) I am able to achieve results, but for some reason I have a ? listed as part of the string.
public static string SerializeToString(object obj)
{
XmlSerializer serializer = new XmlSerializer(obj.GetType());
XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
ns.Add("", "");
MemoryStream ms = new MemoryStream();
XmlWriterSettings settings = new XmlWriterSettings();
settings.OmitXmlDeclaration = true;
settings.Encoding = Encoding.Unicode;
XmlWriter writer = XmlWriter.Create(ms, settings);
serializer.Serialize(writer, obj, ns);
return Encoding.Unicode.GetString(ms.ToArray());
}
the resulting string is:
?<ContentQueryCriteria><Type>1</Type><Value>NAVS500</Value><Condition>1</Condition></ContentQueryCriteria>
if I set OmitXmlDeclaration = false I get the following string:
?<?xml version="1.0" encoding="utf-16"?><ContentQueryCriteria><Type>1</Type><Value>NAVS500</Value><Condition>1</Condition></ContentQueryCriteria>
Can anyone help me determine why the extra ? is there and how I can remove it?
Working SerializeToString method with no BOM
public static string SerializeToString(object obj)
{
XmlSerializer serializer = new XmlSerializer(obj.GetType());
XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
ns.Add("", "");
MemoryStream ms = new MemoryStream();
XmlWriterSettings settings = new XmlWriterSettings();
settings.OmitXmlDeclaration = true;
settings.Encoding = new UnicodeEncoding(bigEndian: false, byteOrderMark: false);
XmlWriter writer = XmlWriter.Create(ms, settings);
serializer.Serialize(writer, obj, ns);
return Encoding.Unicode.GetString(ms.ToArray());
}

You are seeing BOM (byte order mask) as first character in your string converted from stream's byte array.
Turn off outputting BOM and you'll be fine.
Use encoding object that does not generate BOM: UnicodeEncoding
settings.Encoding = new UnicodeEncoding(bigEndian:false,byteOrderMark:true)

remove encoding from xmlserializer

I am using the following code to create an xml document -
XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
ns.Add("", "");
new XmlSerializer(typeof(docket)).Serialize(Console.Out, i, ns);
this works great in creating the xml file with no namespace attributes. i would like to also have no encoding attribute in the root element, but I cannot find a way to do it. Does anyone have any idea if this can be done?
Thanks

Old answer removed and update with new solution:
Assuming that it's ok to remove the xml declaration completly, because it makes not much sense without the encoding attribute:
XmlSerializerNamespaces ns = new XmlSerializerNamespaces(); ns.Add("", "");
using (XmlWriter writer = XmlWriter.Create(Console.Out, new XmlWriterSettings { OmitXmlDeclaration = true}))
{
new XmlSerializer(typeof (SomeType)).Serialize(writer, new SomeType(), ns);
}

To remove encoding from XML header pass TextWriter with null encoding to XmlSerializer:
MemoryStream ms = new MemoryStream();
XmlTextWriter w = new XmlTextWriter(ms, null);
s.Serialize(w, vs);
Explanation
XmlTextWriter uses encoding from TextWriter passed in constructor:
// XmlTextWriter constructor
public XmlTextWriter(TextWriter w) : this()
{
this.textWriter = w;
this.encoding = w.Encoding;
..
It uses this encoding when generating XML:
// Snippet from XmlTextWriter.StartDocument
if (this.encoding != null)
{
builder.Append(" encoding=");
...

string withEncoding;
using (System.IO.MemoryStream memory = new System.IO.MemoryStream()) {
using (System.IO.StreamWriter writer = new System.IO.StreamWriter(memory)) {
serializer.Serialize(writer, obj, null);
using (System.IO.StreamReader reader = new System.IO.StreamReader(memory)) {
memory.Position = 0;
withEncoding= reader.ReadToEnd();
}
}
}
string withOutEncoding= withEncoding.Replace("<?xml version=\"1.0\" encoding=\"utf-8\"?>", "");

Credit to this blog for helping me with my code
http://blog.dotnetclr.com/archive/2008/01/29/removing-declaration-and-namespaces-from-xml-serialization.aspx
here's my solution, same idea, but in VB.NET and a little clearer in my opinion.
Dim sw As StreamWriter = New, StreamWriter(req.GetRequestStream,System.Text.Encoding.ASCII)
Dim xSerializer As XmlSerializer = New XmlSerializer(GetType(T))
Dim nmsp As XmlSerializerNamespaces = New XmlSerializerNamespaces()
nmsp.Add("", "")
Dim xWriterSettings As XmlWriterSettings = New XmlWriterSettings()
xWriterSettings.OmitXmlDeclaration = True
Dim xmlWriter As XmlWriter = xmlWriter.Create(sw, xWriterSettings)
xSerializer.Serialize(xmlWriter, someObjectT, nmsp)

How to create an XML document from a .NET object?

I have the following variable that accepts a file name:
var xtr = new XmlTextReader(xmlFileName) { WhitespaceHandling = WhitespaceHandling.None };
var xd = new XmlDocument();
xd.Load(xtr);
I would like to change it so that I can pass in an object. I don't want to have to serialize the object to file first.
Is this possible?
Update:
My original intentions were to take an xml document, merge some xslt (stored in a file), then output and return html... like this:
public string TransformXml(string xmlFileName, string xslFileName)
{
var xtr = new XmlTextReader(xmlFileName) { WhitespaceHandling = WhitespaceHandling.None };
var xd = new XmlDocument();
xd.Load(xtr);
var xslt = new System.Xml.Xsl.XslCompiledTransform();
xslt.Load(xslFileName);
var stm = new MemoryStream();
xslt.Transform(xd, null, stm);
stm.Position = 1;
var sr = new StreamReader(stm);
xtr.Close();
return sr.ReadToEnd();
}
In the above code I am reading in the xml from a file. Now what I would like to do is just work with the object, before it was serialized to the file.
So let me illustrate my problem using code
public string TransformXMLFromObject(myObjType myobj , string xsltFileName)
{
// Notice the xslt stays the same.
// Its in these next few lines that I can't figure out how to load the xml document (xd) from an object, and not from a file....
var xtr = new XmlTextReader(xmlFileName) { WhitespaceHandling = WhitespaceHandling.None };
var xd = new XmlDocument();
xd.Load(xtr);
}

You want to turn an arbitrary .NET object into a serialized XML string? Nothing simpler than that!! :-)
public string SerializeToXml(object input)
{
XmlSerializer ser = new XmlSerializer(input.GetType(), "http://schemas.yournamespace.com");
string result = string.Empty;
using(MemoryStream memStm = new MemoryStream())
{
ser.Serialize(memStm, input);
memStm.Position = 0;
result = new StreamReader(memStm).ReadToEnd();
}
return result;
}
That should to it :-) Of course you might want to make the default XML namespace configurable as a parameter, too.
Or do you want to be able to create an XmlDocument on top of an existing object?
public XmlDocument SerializeToXmlDocument(object input)
{
XmlSerializer ser = new XmlSerializer(input.GetType(), "http://schemas.yournamespace.com");
XmlDocument xd = null;
using(MemoryStream memStm = new MemoryStream())
{
ser.Serialize(memStm, input);
memStm.Position = 0;
XmlReaderSettings settings = new XmlReaderSettings();
settings.IgnoreWhitespace = true;
using(var xtr = XmlReader.Create(memStm, settings))
{
xd = new XmlDocument();
xd.Load(xtr);
}
}
return xd;
}

You can serialize directly into the XmlDocument:
XmlDocument doc = new XmlDocument();
XPathNavigator nav = doc.CreateNavigator();
using (XmlWriter w = nav.AppendChild())
{
XmlSerializer ser = new XmlSerializer(typeof(MyType));
ser.Serialize(w, myObject);
}

Expanding on #JohnSaunders solution I wrote the following generic function:
public XmlDocument SerializeToXml<T>(T source) {
var document = new XmlDocument();
var navigator = document.CreateNavigator();
using (var writer = navigator.AppendChild()) {
var serializer = new XmlSerializer(typeof(T));
serializer.Serialize(writer, source);
}
return document;
}

disabling namespace attributes in serialization

Am using following code to deserialize an object,
using (MemoryStream memoryStream = new MemoryStream())
{
try
{
XmlWriterSettings writerSettings1 = new XmlWriterSettings();
writerSettings1.CloseOutput = false;
writerSettings1.Encoding = System.Text.Encoding.UTF8;
writerSettings1.Indent = false;
writerSettings1.OmitXmlDeclaration = true;
XmlWriter writer1 = XmlWriter.Create(memoryStream, writerSettings1);
XmlSerializer xs1 = new XmlSerializer(obj.GetType(), string.Empty);
xs1.UnknownAttribute += new XmlAttributeEventHandler(xs1_UnknownAttribute);
xs1.UnknownElement += new XmlElementEventHandler(xs1_UnknownElement);
xs1.UnknownNode += new XmlNodeEventHandler(xs1_UnknownNode);
xs1.UnreferencedObject += new UnreferencedObjectEventHandler(xs1_UnreferencedObject);
xs1.Serialize(writer1, obj);
writer1.Close();
}
catch (InvalidOperationException)
{
return null;
}
memoryStream.Position = 0;
serializeObjectDoc.Load(memoryStream);
return serializeObjectDoc.DocumentElement;
After this when i check the returning node i get two extra attributes
{Attribute, Name="xmlns:xsi", Value="http://www.w3.org/2001/XMLSchema-instance"} object {System.Xml.XmlAttribute}
{Attribute, Name="xmlns:xsd", Value="http://www.w3.org/2001/XMLSchema"} object {System.Xml.XmlAttribute}
I want to know how to disable these two attributes

XmlSerializerNamespaces to the rescue; a simple (but complete) example:
using System.Xml.Serialization;
using System;
public class Foo
{
public string Bar { get; set; }
static void Main()
{
XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
ns.Add("", "");
XmlSerializer ser = new XmlSerializer(typeof(Foo));
ser.Serialize(Console.Out, new Foo { Bar = "abc" }, ns);
}
}