XmlSerializer throws an InvalidOperationException when there is a namespace prefix in the attribute

Question

I am trying to read an XML file containing the following element:

<ho:CODED-TYPE ho:BASE-DATA-TYPE="A_UINT16" CATEGORY="STANDARD-LENGTH-TYPE" ENCODING="UNSIGNED">

My class for describing this node is as follows:

public ref class FIBEXCodedType 
 {
 public:
  [XmlAttribute("ho:BASE-DATA-TYPE")]
  property String^ BaseDataType;

  [XmlAttribute("CATEGORY")]
  property String^ Category;

  [XmlAttribute("ENCODING")]
  property String^ Encoding;

  FIBEXCodedType(void);
 };

I get an InvalidOperationException from XmlSerializer.ctor telling me:

"Ungültiges Namenszeichen in" ho: BASE-DATA-TYPE "(this can be translated as" invalid character in: "ho: BASE-DATA-TYPE").

I also tried the following:

[XmlAttribute("BASE-DATA-TYPE", Namespace="http://www.asam.net/xml")]
property String^ BaseDataType;

But that didn't work either. This time without an error message, but unit test does not allow me to say that the property is still set to "null".

I am completely stuck with this. Therefore any help is appreciated

early

EDIT: some more XML

<?xml version="1.0" ?>
<fx:FIBEX xmlns:fx="http://www.asam.net/xml/fbx" xmlns:ho="http://www.asam.net/xml" xmlns:can="http://www.asam.net/xml/fbx/can" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="fibex4can.xsd" VERSION="3.1.0">

<fx:CODING ID="codingSpeed">
    <ho:SHORT-NAME>CodingSpeed</ho:SHORT-NAME>
    <ho:DESC>Coding for speed values within this system.</ho:DESC>
    <ho:CODED-TYPE ho:BASE-DATA-TYPE="A_UINT16" CATEGORY="STANDARD-LENGTH-TYPE" ENCODING="UNSIGNED">
    <ho:BIT-LENGTH>16</ho:BIT-LENGTH>
    </ho:CODED-TYPE>
</fx:CODING>

Answer 1

OP

. , XML. : . , . , ( ).

, null. , . , , . :

<!-- this works (if namespaces are indeed different -->
<ho:CODED-TYPE fx:BASE=DATA-TYPE="A_UINT16"...>

<!-- this works, unqualified name takes namespace of parent element -->
<ho:CODED-TYPE BASE=DATA-TYPE="A_UINT16"...>

<!-- this fails, because XmlSerializer does not expect qualified attributes -->
<ho:CODED-TYPE ho:BASE=DATA-TYPE="A_UINT16"...>

. n MSDN, . . XML ( XmlSchemaForm.Qualified):

[XmlRoot(ElementName = "FIBEX", Namespace = "http://www.asam.net/xml/fbx")]
public class FIBEX
{
    [XmlElement("CODING", Namespace = "http://www.asam.net/xml/fbx")]
    public FIBEXCoding Coding { get; set; }
}

public class FIBEXCoding
{
    [XmlElement("SHORT-NAME", Namespace = "http://www.asam.net/xml")]
    public string ShortName { get; set; }

    [XmlElement("DESC", Namespace = "http://www.asam.net/xml")]
    public string ShortDescription { get; set; }

    [XmlElement("CODED-TYPE", Namespace = "http://www.asam.net/xml")]
    public FIBEXCodedType Codedtype { get; set; }
}

public class FIBEXCodedType
{

    [XmlAttribute("BASE-DATA-TYPE", 
        Namespace = "http://www.asam.net/xml",
        Form=XmlSchemaForm.Qualified)]
    public string BaseDataType { get; set; }

    [XmlAttribute("CATEGORY")]
    public string Category { get; set; }

    [XmlAttribute("ENCODING")]
    public string Encoding { get; set; }

    [XmlElement("BIT-LENGTH", Namespace = "http://www.asam.net/xml")]
    public int BitLength { get; set; }
}