XmlSerializer won't serialize IEnumerable

Question

I have an invocation logger that is intended to record all method calls along with the parameters associated with the method using XmlSerializer. It works well for most of t

Answer 1

Basically an XmlSerializer can't serialize an interface. The solution, then, is to give it a concrete instance to serialize. Depending on how your invocation logger works, I would consider using

var serializer = new XmlSerializer(value.GetType());

Answer 2

The way you serialize an IEnumerable property is with a surrogate property

[XmlRoot]
public class Entity {
   [XmlIgnore]
   public IEnumerable<Foo> Foo { get; set; }

   [XmlElement, Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
   public List<Foo> FooSurrogate { get { return Foo.ToList(); } set { Foo = value; } }
}

It's ugly, but it gets the job done. The nicer solution is to write a surrogate class (i.e. EntitySurrogate).

Answer 3

To be XML serializable, types which inherit from IEnumerable must have an implementation of Add(System.Object) at all levels of their inheritance hierarchy. {your class} does not implement Add(System.Object).

implement the Add() function, you might solve the problem

Answer 4

I don't think you'll be able to serialize that. Try converting the IEnumerable to a List and then you will be able to serialize.

Answer 5

XmlSerializer does not support this. Try YAXLib for these kinds serializations.

Answer 6

Maybe not the best way, but it worked for me. I created a method that makes serialization.

Use

var xml = Util.ObjetoToXML(obj, null, null).OuterXml;

method

        public static XmlDocument ObjetoToXML(object obj, XmlDocument xmlDocument, XmlNode rootNode)
    {

        if (xmlDocument == null)
            xmlDocument = new XmlDocument();

        if (obj == null) return xmlDocument;

        Type type = obj.GetType();

        if (rootNode == null) { 
            rootNode = xmlDocument.CreateElement(string.Empty, type.Name, string.Empty);
            xmlDocument.AppendChild(rootNode);
        }

        if (type.IsPrimitive || type == typeof(Decimal) || type == typeof(String) || type == typeof(DateTime))
        {

            // Simples types
            if (obj != null)
                rootNode.InnerText = obj.ToString();

        }
        else if (type.IsGenericType && type.GetGenericTypeDefinition() == typeof(List<>))
        {
            // Genericis types

            XmlNode node = null;

            foreach (var item in (IEnumerable)obj)
            {
                if (node == null)
                {
                    node = xmlDocument.CreateElement(string.Empty, item.GetType().Name, string.Empty);
                    node = rootNode.AppendChild(node);
                }


                ObjetoToXML(item, xmlDocument, node);
            }

        }
        else
        {

            // Classes types
            foreach (var propertie in obj.GetType().GetProperties())
            {

                XmlNode node = xmlDocument.CreateElement(string.Empty, propertie.Name, string.Empty);
                node = rootNode.AppendChild(node);
                var valor = propertie.GetValue(obj, null);

                ObjetoToXML(valor, xmlDocument, node);
            }

        }


        return xmlDocument;

    }