XmlSerializer empty properties in class with interface

Question

I am having an API XML response, that looks like:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<artists itemsPerPage="30">
  <artist id="a0d9633b">
    <url>http://www.somesite.com/3df8daf.html</url>
  </artist>
</artists>

For deserializing it I use classes:

[SerializableAttribute]
[XmlTypeAttribute(TypeName = "result")]
public abstract class Result
{
    private int _itemsPerPage;

    [XmlAttributeAttribute(AttributeName = "itemsPerPage")]
    public int ItemsPerPage
    {
        get { return this._itemsPerPage; }
        set { this._itemsPerPage = value; }
    }
}

[SerializableAttribute]
[XmlTypeAttribute(TypeName = "artists")]
[XmlRootAttribute(ElementName = "artists")]
public class Artists : Result, IEnumerable<Artist>
{
    private List<Artist> _list;

    [XmlElementAttribute(ElementName = "artist")]
    public List<Artist> List
    {
        get { return this._list; }
        set { this._list = value; }
    }

    public Artists()
    {
        _list = new List<Artist>();
    }

    public void Add(Artist item)
    {
        _list.Add(item);
    }

    IEnumerator IEnumerable.GetEnumerator() { return _list.GetEnumerator(); }

    public IEnumerator<Artist> GetEnumerator()
    {
        foreach (Artist artist in _list)
            yield return artist;
    }
}

[SerializableAttribute]
[XmlTypeAttribute(TypeName = "artist")]
[XmlRootAttribute(ElementName = "artist")]
public class Artist
{
    private string _mbid;
    private string _url;

    [XmlAttributeAttribute(AttributeName = "mbid")]
    public string MBID
    {
        get { return this._mbid; }
        set { this._mbid = value; }
    }

    [XmlElementAttribute(ElementName = "url")]
    public string Url
    {
        get { return this._url; }
        set { this._url = value; }
    }

    public Artist() { }
}

And this is how I do deserialization:

XmlSerializer serializer = new XmlSerializer(typeof(Artists));
Artists result = (Artists)serializer.Deserialize(new StreamReader("artists.xml"));

So, the problem is, that when I do deserialization, ItemsPerPage doesn't have a needed (30) value (it has default 0). However, if I remove IEnumerable<Artist> interface and deserialize Artists, the value will appear. I can remove interface and leaves Artists with only IEnumerator<Artist> GetEnumerator() method, so everything will be fine, Artists still can be foreach'ed, but will no longer be IEnumerable<Artist>. Which is not what I want. The problem is not in base class, because I can transfer property ItemsPerPage to Artists class, and deserialization result will be the same.

Any ideas how I can deserialize ItemsPerPage value with Artists still being IEnumerable<Artist>?

This is the documented behavior of `XmlSerializer`. See [When a class is inherited from List<>, XmlSerializer doesn't serialize other attributes](https://stackoverflow.com/questions/5069099). For one workaround, see [How to serialize an ICollection that also has read/write properties to XML](https://stackoverflow.com/questions/34221481). — dbc, Jul 21 '16 at 15:35
Do those two answers suffice, or do you need additional help? — dbc, Jul 21 '16 at 17:06
@dbc seems that the only solution is to implement `IXmlSerializable`. `DataContractSerializer` doesn't support XML atrributes and as I stated I want to keep Artists being `IEnumerable`, so changing class won't work too. — Konstantin K., Jul 22 '16 at 07:46

XmlSerializer empty properties in class with interface

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