RestSharp Deserialize返回空属性，但xml.deserialize测试有效

Question

EDIT : the moment I asked the question I thougt of trying something.. I've set XmlNamespace property on the request and that did the trick..

request.XmlNamespace = "http://musicbrainz.org/ns/mmd-2.0#";

But I don't really understand as to why...

Next problem is getting RestSharp to recognize xml atributes as object properties

---

I've been going over this for the most of the weekend and I just don't get it to work.

I'm trying to write a wrapper round a RestFul webservice (MusicBrainz). I'm testing with a simple example : get details of one artist and put it in a custom Artist object.

When I do a Execute on the RestClient it ends ok but my object properties are null.. But when I test the deserialization with the XmlDeserializer the objectproperties are filled (But not for properties that correspond to an attribute, but I'll tackle that later)

What happens between deserialization of the response and putting the object in response.data ? Quite possible it is a "newbie" error I'm making as this are my first steps with RestSharp..

Help would be much appreciated..

Returnded xml :

<metadata>
   <artist type="Group" id="f1548c5b-329e-4036-921c-02213a04b525">
       <name>Uriah Heep</name>
           <sort-name>Uriah Heep</sort-name>
           <country>GB</country>
           <life-span>
               <begin>1970</begin>
           </life-span>
    </artist>
</metadata>

My class :

public class Artist
{
    public int Id { get; set; }
    public string Type { get; set; }
    public string Name { get; set; }
    public string SortName { get; set; }
    public string Country { get; set; }

}

In the following code output properties are filled

var output = xml.Deserialize<Artist>(response);

But the same response does not fill properties when calling

var response = client.Execute<T>(request);

Complete code (I've put the test code in the generic method for sake of simplicity) :

public T Execute<T>(RestRequest request) where T : new()
{
    var client = new RestClient();
    client.BaseUrl = BaseUrl;
    client.Authenticator = null;

    //does not fill properties 
    var response = client.Execute<T>(request);

    if (response.ErrorException != null)
    {
        throw response.ErrorException;
    }
    var xml = new XmlDeserializer();

    //fills properties
    var output = xml.Deserialize<Artist>(response);

    return response.Data;
}

Answer 1

This happens because Execute method, after receiving response, tries to negotiate it based on the request's RootElement and XmlNamespace properties and copies them to the XmlDeserializer .

Here's a code from RestClient :

     handler.RootElement = request.RootElement;
     handler.DateFormat = request.DateFormat;
     handler.Namespace = request.XmlNamespace;
     response.Data = handler.Deserialize<T>(raw);

If you pass a RestRequest with a mismatching XmlNamespace, RestSharp's XmlDeserializer (that uses XDocument behind the scenes) won't be able to map response XML to an object properties and you will get default/null values instead.

Now for default implementation (when you create XmlDeserializer manually), if you don't set a XmlNamespace, deserializer will do an auto-detection that basically ignores all namespaces in the response and maps all properties only by their names.

See source code from XmlDeserializer :

     // autodetect xml namespace
     if (!Namespace.HasValue())
     {
         RemoveNamespace(doc);
     }

Taking all above into account, it's clear why it started working after you explicitly set XmlNamespace property to a matching namespace in your request object with this line:

     request.XmlNamespace = "http://musicbrainz.org/ns/mmd-2.0#";

Execute method copied namespace into deserializer and it mapped XML to object appropriately.