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c#jsonserializationjson.netdeserialization

Json.NET: Deserializing nested dictionaries


When deserializing an object to a Dictionary (JsonConvert.DeserializeObject<IDictionary<string,object>>(json)) nested objects are deserialized to JObjects. Is it possible to force nested objects to be deserialized to Dictionarys?


Solution

  • I found a way to convert all nested objects to Dictionary<string,object> by providing a CustomCreationConverter implementation:

    class MyConverter : CustomCreationConverter<IDictionary<string, object>>
    {
        public override IDictionary<string, object> Create(Type objectType)
        {
            return new Dictionary<string, object>();
        }
    
        public override bool CanConvert(Type objectType)
        {
            // in addition to handling IDictionary<string, object>
            // we want to handle the deserialization of dict value
            // which is of type object
            return objectType == typeof(object) || base.CanConvert(objectType);
        }
    
        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
        {
            if (reader.TokenType == JsonToken.StartObject
                || reader.TokenType == JsonToken.Null)
                return base.ReadJson(reader, objectType, existingValue, serializer);
    
            // if the next token is not an object
            // then fall back on standard deserializer (strings, numbers etc.)
            return serializer.Deserialize(reader);
        }
    }
    
    class Program
    {
        static void Main(string[] args)
        {
            var json = File.ReadAllText(@"c:\test.json");
            var obj = JsonConvert.DeserializeObject<IDictionary<string, object>>(
                json, new JsonConverter[] {new MyConverter()});
        }
    }
    

    Documentation: CustomCreationConverter with Json.NET