将包含IList的对象序列化为XML

Question

So I have an Object called FormType. It contains some strings, booleans etc.

But FormType also contains this:

   private IList<FormTypeVersion> _versions = new List<FormTypeVersion>();

    public virtual IList<FormTypeVersion> Versions
    {
        get { return _versions; }
        set { _versions = value; }
    }

Is this why I am getting this error:

{"Cannot serialize member 'Domain.FormType.Versions' of type 'System.Collections.Generic.IList`1

Also - FormTypeVersion also contains some ILists.

How can I get round this error, it happens at this line:

var xm = new XmlSerializer(typeof(T));

Answer 1

The XmlSerializer cannot deserialize interfaces (unless you want to implement IXmlSerializable yourself on the FormType object). That is why you are seeing that exception.

If you change your IList to List it should work like in the following example:

[Serializable]
public class FormType
{
    private List<FormTypeVersion> _versions = new List<FormTypeVersion>();

    public virtual List<FormTypeVersion> Versions
    {
        get { return _versions; }
        set { _versions = value; }
    }
}

If you don't have the luxury to change your type from IList to List, then the cleanest approach is to implement IXmlSerializable . There are other solutions using abstract types, reflection and similar, but i wouldn't call that clean.