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JSON .NET Custom Name Resolver voor sub-eigenschappen

Wat u kunt doen, is voor de betreffende eigenschap een aangepaste JsonConverter die de betreffende eigenschapswaarde serialiseert met een andere JsonSerializer gemaakt met een andere contractoplosser, zoals:

public class AlternateContractResolverConverter : JsonConverter
{
    [ThreadStatic]
    static Stack<Type> contractResolverTypeStack;

    static Stack<Type> ContractResolverTypeStack { get { return contractResolverTypeStack = (contractResolverTypeStack ?? new Stack<Type>()); } }

    readonly IContractResolver resolver;

    JsonSerializerSettings ExtractAndOverrideSettings(JsonSerializer serializer)
    {
        var settings = serializer.ExtractSettings();
        settings.ContractResolver = resolver;
        settings.CheckAdditionalContent = false;
        if (settings.PreserveReferencesHandling != PreserveReferencesHandling.None)
        {
            // Log an error throw an exception?
            Debug.WriteLine(string.Format("PreserveReferencesHandling.{0} not supported", serializer.PreserveReferencesHandling));
        }
        return settings;
    }

    public AlternateContractResolverConverter(Type resolverType)
    {
        if (resolverType == null)
            throw new ArgumentNullException("resolverType");
        resolver = (IContractResolver)Activator.CreateInstance(resolverType);
        if (resolver == null)
            throw new ArgumentNullException(string.Format("Resolver type {0} not found", resolverType));
    }

    public override bool CanRead { get { return ContractResolverTypeStack.Count == 0 || ContractResolverTypeStack.Peek() != resolver.GetType(); } }
    public override bool CanWrite { get { return ContractResolverTypeStack.Count == 0 || ContractResolverTypeStack.Peek() != resolver.GetType(); } }

    public override bool CanConvert(Type objectType)
    {
        throw new NotImplementedException("This contract resolver is intended to be applied directly with [JsonConverter(typeof(AlternateContractResolverConverter), typeof(SomeContractResolver))] or [JsonProperty(ItemConverterType = typeof(AlternateContractResolverConverter), ItemConverterParameters = ...)]");
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        using (ContractResolverTypeStack.PushUsing(resolver.GetType()))
            return JsonSerializer.CreateDefault(ExtractAndOverrideSettings(serializer)).Deserialize(reader, objectType);
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        using (ContractResolverTypeStack.PushUsing(resolver.GetType()))
            JsonSerializer.CreateDefault(ExtractAndOverrideSettings(serializer)).Serialize(writer, value);
    }
}

internal static class JsonSerializerExtensions
{
    public static JsonSerializerSettings ExtractSettings(this JsonSerializer serializer)
    {
        // There is no built-in API to extract the settings from a JsonSerializer back into JsonSerializerSettings,
        // so we have to fake it here.
        if (serializer == null)
            throw new ArgumentNullException("serializer");
        var settings = new JsonSerializerSettings
        {
            CheckAdditionalContent = serializer.CheckAdditionalContent,
            ConstructorHandling = serializer.ConstructorHandling,
            ContractResolver = serializer.ContractResolver,
            Converters = serializer.Converters,
            Context = serializer.Context,
            Culture = serializer.Culture,
            DateFormatHandling = serializer.DateFormatHandling,
            DateFormatString = serializer.DateFormatString,
            DateParseHandling = serializer.DateParseHandling,
            DateTimeZoneHandling = serializer.DateTimeZoneHandling,
            DefaultValueHandling = serializer.DefaultValueHandling,
            EqualityComparer = serializer.EqualityComparer,
            // No Get access to the error event, so it cannot be copied.
            // Error = += serializer.Error
            FloatFormatHandling = serializer.FloatFormatHandling,
            FloatParseHandling = serializer.FloatParseHandling,
            Formatting = serializer.Formatting,
            MaxDepth = serializer.MaxDepth,
            MetadataPropertyHandling = serializer.MetadataPropertyHandling,
            MissingMemberHandling = serializer.MissingMemberHandling,
            NullValueHandling = serializer.NullValueHandling,
            ObjectCreationHandling = serializer.ObjectCreationHandling,
            ReferenceLoopHandling = serializer.ReferenceLoopHandling,
            // Copying the reference resolver doesn't work in the default case, since the
            // actual BidirectionalDictionary<string, object> mappings are held in the 
            // JsonSerializerInternalBase.
            // See https://github.com/JamesNK/Newtonsoft.Json/blob/master/Src/Newtonsoft.Json/Serialization/DefaultReferenceResolver.cs
            ReferenceResolverProvider = () => serializer.ReferenceResolver,
            PreserveReferencesHandling = serializer.PreserveReferencesHandling,
            StringEscapeHandling = serializer.StringEscapeHandling,
            TraceWriter = serializer.TraceWriter,
            TypeNameHandling = serializer.TypeNameHandling,
            // Changes in Json.NET 10.0.1
            //TypeNameAssemblyFormat was obsoleted and replaced with TypeNameAssemblyFormatHandling in Json.NET 10.0.1
            //TypeNameAssemblyFormat = serializer.TypeNameAssemblyFormat,
            TypeNameAssemblyFormatHandling = serializer.TypeNameAssemblyFormatHandling,
            //Binder was obsoleted and replaced with SerializationBinder in Json.NET 10.0.1
            //Binder = serializer.Binder,
            SerializationBinder = serializer.SerializationBinder,
        };
        return settings;
    }
}

public static class StackExtensions
{
    public struct PushValue<T> : IDisposable
    {
        readonly Stack<T> stack;

        public PushValue(T value, Stack<T> stack)
        {
            this.stack = stack;
            stack.Push(value);
        }

        // By using a disposable struct we avoid the overhead of allocating and freeing an instance of a finalizable class.
        public void Dispose()
        {
            if (stack != null)
                stack.Pop();
        }
    }

    public static PushValue<T> PushUsing<T>(this Stack<T> stack, T value)
    {
        if (stack == null)
            throw new ArgumentNullException();
        return new PushValue<T>(value, stack);
    }
}

Gebruik het dan als volgt:

public class RootObject
{
    public string Name { get; set; }
    public DateTime DateCreated { get; set; }

    [JsonProperty(NamingStrategyType = typeof(DefaultNamingStrategy))]
    [JsonConverter(typeof(AlternateContractResolverConverter), typeof(DefaultContractResolver))]
    public SomeDocument SomeDocument { get; set; }
}

public class SomeDocument
{
    public string MyFirstProperty { get; set; }
    public string mysecondPROPERTY { get; set; }
    public AnotherRandomSubdoc another_random_subdoc { get; set; }
}

public class AnotherRandomSubdoc
{
    public string evenmoredata { get; set; }
    public DateTime DateCreated { get; set; }
}

(Hier neem ik aan dat je de "SomeDocument" . wilt eigenschapnaam moet letterlijk worden geserialiseerd, ook al was dit niet helemaal duidelijk uit uw vraag. Om dat te doen, gebruik ik JsonPropertyAttribute.NamingStrategyType van Json.NET 9.0.1. Als u een eerdere versie gebruikt, moet u de eigenschapsnaam expliciet instellen.)

De resulterende JSON is dan:

{
  "name": "Question 40597532",
  "dateCreated": "2016-11-14T05:00:00Z",
  "SomeDocument": {
    "MyFirstProperty": "my first property",
    "mysecondPROPERTY": "my second property",
    "another_random_subdoc": {
      "evenmoredata": "even more data",
      "DateCreated": "2016-11-14T05:00:00Z"
    }
  }
}

Merk op dat deze oplossing NIET goed werkt met het behouden van objectreferenties . Als je ze nodig hebt om samen te werken, moet je mogelijk een op stacks gebaseerde aanpak overwegen, vergelijkbaar met die van Json.NET serialiseren op diepte en attribuut

Demo viool hier .

Heb je trouwens overwogen om deze JSON op te slaan als een onbewerkte tekenreeks, zoals in het antwoord op deze vraag ?



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