Inbound JSON to WebApi returning 500 error

Question

Hello everyone and thanks for the help in advance. I am working on a Asp.Net Core WebApi that receives json from a third party external vendor. Here is a sample message returned:

{"?xml":{"@version":"1.0","@encoding":"utf-8"},"Message":{"@xmlns:xsi":"http://www.w3.org/2001/XMLSchema-instance","@DatatypesVersion":"20170715","@TransportVersion":"20170715","@TransactionDomain":"SCRIPT","@TransactionVersion":"20170715","@StructuresVersion":"20170715","@ECLVersion":"20170715","Header":{"To":{"@Qualifier":"D","#text":"D122190:C111392"},"From":{"@Qualifier":"M","#text":"WEX"},"MessageID":"6fe89f5815c74dd793630563380ad822","RelatesToMessageID":"12320263","SentTime":"2024-08-24T00:19:14.76364Z","Security":{"UsernameToken":{"Username":"WEX","Password":{"@Type":"PasswordDigest","#text":"XXXX"}}},"SenderSoftware":{"SenderSoftwareDeveloper":"WENO_DEV","SenderSoftwareProduct":"WEX","SenderSoftwareVersionRelease":"V1"}},"Body":{"Verify":{"VerifyStatus":{"Code":"010","Description":"NewRx sent by the WOL account method."}}}}}

I'm not really sure why they are returning the segment

{"?xml":{"@version":"1.0","@encoding":"utf-8"}

and I am not sure how to work around it given

public class Root
{
public ?xml ?xml { get; set; }
public Message Message { get; set; }
}

throws a syntax error and removing the question mark des not map the data correctly. Any help would be appreciated.

Answer 1

Hi @Kmcnet,

This JSON structure represents XML metadata, you could try following steps to deserialize the json.

Install package Microsoft.AspNetCore.Mvc.NewtonsoftJson, then specify the property name by using Newtonsoft.Json;

    public class Root
    {
        [JsonProperty("?xml")]
        public XmlDetails Xml { get; set; }
    }
    public class XmlDetails
    {
        [JsonProperty("@version")]
        public string Version { get; set; }
        [JsonProperty("@encoding")]
        public string Encoding { get; set; }
    }

Set up default serializer in program.cs

builder.Services.AddControllers().AddNewtonsoftJson();

Test result:

{"?xml":{"@version":"1.0","@encoding":"utf-8"}}

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Answer 2

if you only need to deserialize then you ignore the special characters. the deserializer will bind by ignoring the invalid characters in the name. copy your sample json, then in VS paste special -> paste as json classes

then its just:

var obj = System.Text.Json.JsonSerializer.Deserialize<Rootobject>(jsonString);

if you need to serialize, then you will need to define the json property names (I'd probably do this anyway):

     public class Rootobject
     {
         [System.Text.Json.Serialization.JsonPropertyName("?xml")]
         public Xml xml { get; set; }
         public Message Message { get; set; }
     }