XmlSerializer没有序列化自定义类型

Question

I am trying to serialize by following code

var data = argsPerCall.ToArray();
var knownTypes = new[] { typeof(int), typeof(int),  
                         typeof(string), typeof(McPosition)};

var serializer = new XmlSerializer(data.GetType(), knownTypes);
// Writing the file requires a TextWriter.
var myStreamWriter = new StreamWriter(filename);
serializer.Serialize(myStreamWriter, data);
myStreamWriter.Close();

I am having an issue with McPosition type.

For following input

5 , 1, "R251" , {1,2,3}

I am getting following serialization

<ArrayOfAnyType>
    <anyType xsi:type="xsd:int">5</anyType>
    <anyType xsi:type="xsd:int">1</anyType>
    <anyType xsi:type="xsd:string">R251</anyType>
    <anyType xsi:type="McPosition" />
  </ArrayOfAnyType>

Any idea why it wasnt serialized correctly ?

EDIT:

public struct McPosition : IComparable<McPosition> {
    private readonly int _station;
    private readonly int _slot;
    private readonly int _subslot;


    public static McPosition Empty = new McPosition(-1, -1, -1);


    public McPosition(int station, int slot, int subslot) {
      _station = station;
      _slot    = slot;
      _subslot = subslot;
    }

etc....

Thanks .

Answer 1

To be serializeable via XmlSerializer , each property on a type must have a public getter and setter (and not be marked [XmlIgnore] nor have a ShouldSerialize*() that returns false, etc). Public fields are also serialized (as long as they aren't readonly ), but exposing fields is even less desirable. XmlSerializer never looks at private members.

I'm guessing (edit: now confirmed by the updated question) that McPosition is an immutable vector, without public setters. That won't work. Options:

• implement IXmlSerializable (not overly nice, to be honest)
• add public setters to McPosition
• use a separate DTO that is fully mutable

Answer 2

You must add public getter and setter for XML serializable fields. Here : Station, Slot and Subslot.