JSON to c# class serialization returns null

Question

I have a webservice, which I want to POST JSON data. I want to serialize the submitted data into a class and some of the serialized data always returns null.

Here is the problematic part of the json:

"contacts": {
        ..."1": {
            "name": "tesz1",
            "phone": "3600000000",
            "email": null,
            "title": null,
            "try_before_reach" : 0
        },
         "2": {
            "name": "tesz1",
            "phone": "3600000000",
            "email": null,
            "title": null,
            "try_before_reach" : 0
        }
    }...

And this is the class :

....
    [DataMember(Name = "contacts")]
    public Dictionary<string, Contact> contacts { get; set; } 

}

[DataContract]
public class Contact
{
    [DataMember(Name = "name")]
    public string name { get; set; }

    [DataMember(Name = "phone")]
    public string phone { get; set; }

    [DataMember(Name = "email")]
    public string email { get; set; }

    [DataMember(Name = "title")]
    public string title { get; set; }
    [DataMember(Name = "try_before_reach")]
    public int try_before_reach { get; set; }
}

The webservice:

[ServiceContract]
public interface IService1
{
    [OperationContract]
    [WebInvoke(Method = "POST", UriTemplate = "/VCC/", BodyStyle = WebMessageBodyStyle.Bare, RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json)]
    Task<WebhookResponse> ResponseAsync(VCCModel request);

}

And the request.Contact returns with null everytime.

Anyone have any idea what the problem might be?

Thank you very much.

By "webservice" you mean a [tag:wcf] web service? Or something else? Please specify the exact framework and version you are using, as different versions use different JSON serializers. — dbc, Jul 30 '20 at 14:50
your class structure looks good. this should be deserialize. How are calling service and code for serialization and deserialization. Please share. — m.k.sharma, Jul 30 '20 at 14:52
Because if you are really using [tag:wcf], then note that the `DataContractJsonSerializer` used by [tag:wcf] serializes dictionaries as key/value arrays not as objects, see [Collections, Dictionaries and Arrays](https://learn.microsoft.com/en-us/dotnet/framework/wcf/feature-details/stand-alone-json-serialization#collections-dictionaries-and-arrays). While it's possible to modify this behavior for standalone serialization, there's no way to pass the necessary setting into WCF. — dbc, Jul 30 '20 at 15:04
Yes, i'm using wcf. Can you suggest me a solution how can i serialize this with DataContractJsonSerializer, or is it possible to replace somehow the serializer? — Attila Lazúr, Jul 30 '20 at 22:11
Can you change the JSON instead? It's much much easier to just format your JSON as required by `DataContractJsonSerializer`. — dbc, Aug 02 '20 at 20:57
Hi, is the problem resolved? If the problem persists, please feel free to let me know. — Ding Peng, Aug 10 '20 at 07:20

Ding Peng · Answer 1 · 2020-08-03T06:19:19.250

According to the information you provided, I did a test but did not encounter the situation you mentioned. I suspect that there may be an error in your request format or your "request.Contact" is Null.Here is my demo:

Class

[DataContract]
public class Contact
{
    [DataMember(Name = "name")]
    public string name { get; set; }

    [DataMember(Name = "phone")]
    public string phone { get; set; }

    [DataMember(Name = "email")]
    public string email { get; set; }

    [DataMember(Name = "title")]
    public string title { get; set; }
    [DataMember(Name = "try_before_reach")]
    public int try_before_reach { get; set; }
}
[DataContract]
public class Respose {
    [DataMember(Name = "contacts")]
    public Dictionary<string, Contact> contacts { get; set; }
}

webservice

        [OperationContract]
        [WebInvoke(Method = "POST", UriTemplate = "/VCC/", BodyStyle = WebMessageBodyStyle.Bare, RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json)]
        Task<Respose> ResponseAsync(string Test);

Implementation class

public Task<Respose> ResponseAsync(string Test)
        {
            Respose respose = new Respose();
            Contact contact1 = new Contact();
            contact1.email = "e1";
            contact1.name = "n1";
            contact1.phone = "p1";
            contact1.title = "t1";
            contact1.try_before_reach = 0;

            Contact contact2 = new Contact();
            contact1.email = "e1";
            contact1.name = "n1";
            contact1.phone = "p1";
            contact1.title = "t1";
            contact1.try_before_reach = 0;
            Dictionary<string, Contact> dict = new Dictionary<string, Contact>() { { "Test1",contact1 }, { "Test2", contact1 } };
            respose.contacts = dict;
            return Task.FromResult<Respose>(respose);
        }

The picture below is the information I got in Postman:

1.You need to check if your request is correct.

2.Check if your "request.Contact" is null.

Feel free to let me know if the problem persists.

JSON to c# class serialization returns null

1 Answers1