Serialize Dictionary as Array (Of Key Value Pairs)

Serialize dictionary as array (of key value pairs)

Ah, it turns out this is as straightforward as I'd hoped. My Dictionary<k,v> is subclassed already and I found that I can annotate it with [JsonArrayAttribute]. That gives me exactly the format I need;

"MyDict": [
  {
    "Key": "Apples",
    "Value": {
        "Taste": 1341181398,
        "Title": "Granny Smith",
    }
  },
  {
    "Key:": "Oranges",
    "Value:": {
        "Taste": 9999999999,
        "Title": "Coxes Pippin",
    }
  },
]

Serialize Dictionary , as array in Json.NET

I was able to get this converter to work.

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using Newtonsoft.Json;
using Newtonsoft.Json.Converters;

public class CustomDictionaryConverter : JsonConverter
{
    public override bool CanConvert(Type objectType)
    {
        return (typeof(IDictionary).IsAssignableFrom(objectType) || 
                TypeImplementsGenericInterface(objectType, typeof(IDictionary<,>)));
    }

    private static bool TypeImplementsGenericInterface(Type concreteType, Type interfaceType)
    {
        return concreteType.GetInterfaces()
               .Any(i => i.IsGenericType && i.GetGenericTypeDefinition() == interfaceType);
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        Type type = value.GetType();
        IEnumerable keys = (IEnumerable)type.GetProperty("Keys").GetValue(value, null);
        IEnumerable values = (IEnumerable)type.GetProperty("Values").GetValue(value, null);
        IEnumerator valueEnumerator = values.GetEnumerator();

        writer.WriteStartArray();
        foreach (object key in keys)
        {
            valueEnumerator.MoveNext();

            writer.WriteStartObject();
            writer.WritePropertyName("key");
            writer.WriteValue(key);
            writer.WritePropertyName("value");
            serializer.Serialize(writer, valueEnumerator.Current);
            writer.WriteEndObject();
        }
        writer.WriteEndArray();
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        throw new NotImplementedException();
    }
}

Here is an example of using the converter:

IDictionary<string, int> dict = new Dictionary<string, int>();
dict.Add("some key", 1);
dict.Add("another key", 5);

string json = JsonConvert.SerializeObject(dict, new CustomDictionaryConverter());
Console.WriteLine(json);

And here is the output of the above:

[{"key":"some key","value":1},{"key":"another key","value":5}]

Json.net serializing a flat object to key-value pair array

If I understand correctly. This is basic serializing. you wanted to serialize your object with key, value pair.

public class Obj
{
    public Obj(string key, string value)
    {
        Key = key;
        Value = value;
    }

    public string Key { get; set; }

    public string Value { get; set; }
}

the main,

 static void Main(string[] args)
 {
     var response = new Dictionary<string, List<Obj>>();
     var inputObjs = new List<Obj>();

     inputObjs.Add(new Obj("prop1", "value1"));
     inputObjs.Add(new Obj("prop2", "value2"));

     response.Add("Inputs", inputObjs);

     var serializedObj = JsonConvert.SerializeObject(response);

     Console.ReadKey();
 }

I used Newtonsoft for serializing the object

you will get this result,

{
    "Inputs": [{
            "key": "prop1",
            "value": "value1"
        },
        {
            "key": "prop2",
            "value": "value2"
        }
    ]
}

JSON convert dictionary to a list of key value pairs

Convert it to a list of key value pairs before passing to the JSON serializer:

JsonConvert.SerializeObject(new List<KeyValuePair<string,string>>(dictionary));

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