JSON model binding with XML Serialisation attributes in Web API

Question

I have an API controller with the following action signature...

[HttpPost]
public HttpResponseMessage DoSearch(SearchParameters parameters)

SearchParameters is not something i can modify, and the decompiled source looks like this...

 [DebuggerStepThrough]
  [XmlRoot("SearchData", IsNullable = false, Namespace = "http://company.com/some/namespace/v1")]
  [GeneratedCode("xsd", "2.0.50727.3038")]
  [DesignerCategory("code")]
  [XmlType(Namespace = "http://company.com/some/namespace/v1")]
  [Serializable]
  public class SearchParameters
  {
    private string[] _searchCodes;

    [XmlArrayItem("SearchCode", IsNullable = false)]
    public string[] SearchCodes
    {
      get
      {
        return this._searchCodes;
      }
      set
      {
        this._searchCodes = value;
      }
    }
  }

I can call the endpoint successfully with an XML payload, but cannot get JSON to work at all. The SearchCodes property is always null.

If i replace the SearchParameters Type with a POCO that has none of the Xml Serialisation attributes on it, it works fine with JSON. This led me to think that the JsonMediaTypeFormatter is unable to match up the property correctly due to the xml serialisation attributes (even though this shouldnt matter, as its JSON, not XML right?). I changed the JsonFormatter to use the DataContract Serializer, but that has made no difference.

httpConfiguration.Formatters.JsonFormatter.UseDataContractJsonSerializer = true;

I tried crafting different structures of JSON to see if i could 'help' it understand, but none of these work either...

{
    "SearchData": {
        "SearchCodes": {
            "SearchCode": [
                "SYAA113F",
                "N0TEXI5T",
                "SYAA112C"
            ]
        }
    }
}


{
    "SearchCodes": {
        "SearchCode": [
            "SYAA113F",
            "N0TEXI5T",
            "SYAA112C"
        ]
    }
}

{
    "SearchCodes":  [
            "SYAA113F",
            "N0TEXI5T",
            "SYAA112C"
        ]
}


{
    "SearchData": {
        "SearchCode": [
            "SYAA113F",
            "N0TEXI5T",
            "SYAA112C"
        ]
    }
}


{
    "SearchCode": [
        "SYAA113F",
        "N0TEXI5T",
        "SYAA112C"
    ]
}

{
    "SearchCodes":  [
            { "SearchCode" : "SYAA113F" },
            { "SearchCode" : "SYAA113F" },
            { "SearchCode" : "SYAA113F" }
        ]
}

How can i debug this further? and what am i missing? What is causing the JSON media formatter to behave differently due to the XML attributes?

Badrinarayanan Lakshmiraghavan · Accepted Answer · 2013-09-02 16:19:17Z

1

Post this JSON and see.

{"_searchCodes":[
        "SYAA113F",
        "N0TEXI5T",
        "SYAA112C"]
}

Remember to set Content-Type: application/json.

answered Sep 2, 2013 at 16:19

Badrinarayanan Lakshmiraghavan

19.3k6 gold badges65 silver badges63 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Baldy Over a year ago

worked a treat. why on earth is it accepting the backing field for binding?

Badrinarayanan Lakshmiraghavan Over a year ago

Because of XML serialization attributes.

Collectives™ on Stack Overflow

JSON model binding with XML Serialisation attributes in Web API

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related