Newtonsoft.Json Deserialize XmlAnyAttribute?

Question

I have a class, that has an object:

[System.CodeDom.Compiler.GeneratedCodeAttribute("System.Xml", "4.0.30319.34283")]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlRootAttribute(Namespace="", IsNullable=true)]
public partial class Scores : baseModel
{
   private System.Xml.XmlAttribute[] anyAttrField;
   /// <remarks/>
   [System.Xml.Serialization.XmlAnyAttributeAttribute()]
   public System.Xml.XmlAttribute[] AnyAttr
  {
      get
      {
         return this.anyAttrField;
      }
      set
      {
         this.anyAttrField = value;
      }
   }
}

From the parent class (snippet of it):

public parial class LandingPage : baseModel
{
    private string projectNameField;
    private Scores scoresField;
    [System.Xml.Serialization.XmlElementAttribute(Form=System.Xml.Schema.XmlSchemaForm.Unqualified)]
    public string projectName
    {
        get { return this.projectNameField; }
        set { this.projectNameField = value; }
    }
    [System.Xml.Serialization.XmlElementAttribute(Form=System.Xml.Schema.XmlSchemaForm.Unqualified)]
    public Scores scores
    {
        get { return this.scoresField; }
        set { this.scoresField = value }
    }
}

The JSON string I'm trying to work with:

{
    "projectName":"PROJECTTEST",
    "scores":{
        "browLocker":100,
        "heavyAd":0,
        "walletRedirection":0
    }
}

NewtonSoft.JsonConvert ignores the scores child fields...

How can I easily convert this to work?

Answer 1

Given that your Scores type has no properties of its own to serialize, you can create a custom JsonConverter for it that converts the XmlAttribute [] array to a Dictionary<string, string> then serializes that dictionary in place of the Scores object:

public class XmlAttributeArrayConverter : JsonConverter
{
    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(XmlAttribute[]);
    } 

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        if (reader.TokenType == JsonToken.Null)
            return null;
        var dict = serializer.Deserialize<Dictionary<string, string>>(reader);
        var doc = new XmlDocument();
        return dict.Select(p => { var a = doc.CreateAttribute(p.Key); a.Value = p.Value; return a; }).ToArray();
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        // TODO: determine how to represent XmlAttribute values with non-empty NamespaceURI - or throw an exception.
        var attributes = (IEnumerable<XmlAttribute>)value;
        var dict = attributes.ToDictionary(a => a.Name, a => a.Value);
        serializer.Serialize(writer, dict);
    }
}

class ScoresConverter : JsonConverter
{
    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(Scores);
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        if (reader.TokenType == JsonToken.Null)
            return null;
        var attributes = (XmlAttribute[])new XmlAttributeArrayConverter().ReadJson(reader, typeof(XmlAttribute[]), null, serializer);
        return new Scores { AnyAttr = attributes };
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        var scores = (Scores)value;
        if (scores.AnyAttr == null)
            writer.WriteNull();
        else
        {
            new XmlAttributeArrayConverter().WriteJson(writer, scores.AnyAttr, serializer);
        }
    }
}

(Note I extracted some of the logic into a separate XmlAttributeArrayConverter in case it might be of use elsewhere.)

Then apply it to Scores as follows:

[JsonConverter(typeof(ScoresConverter))]
public partial class Scores
{
}

Sample fiddle .

Note if one of the XML attributes happens to be in a namespace (most of the time none will be ) then the namespace is not serialized. If your attributes might have namespaces you will need to decide how to convert the attribute's full name to a JSON property name. {namespace}localname would be one possibility, that is what is used by XName.ToString() .