using System;

using System.Net.Http;

// using System.Net.Http.Headers;

using System.Text;

​

using Newtonsoft.Json;

namespace RestClient

{

    public class MicrosoftJsonConverter : JsonConverter

    {

        private readonly JsonSerializer _customSerializer;

​

        public MicrosoftJsonConverter()

        {

            _customSerializer = new JsonSerializer() {DateFormatHandling = DateFormatHandling.MicrosoftDateFormat};

        }

​

        public override bool CanConvert(Type objectType)

        {

            return objectType == typeof(DateTime);

        }

​

        public override object ReadJson(JsonReader reader, Type objectType, object existingValue,

            JsonSerializer serializer)

        {

            return _customSerializer.Deserialize(reader, objectType);

        }

​

        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)

        {

            _customSerializer.Serialize(writer, value);

        }

    }

}

​

public class Program

{

    private static HttpClient httpClient = new HttpClient();

    private static UriBuilder uriBuilder = new UriBuilder();

    public static void Main()

    {

        HttpRequestMessage _reqMessage = new HttpRequestMessage();

​

        _reqMessage.Method = HttpMethod.Post;

        string json = "{\"operationName\":null,\"variables\":{},\"query\":\"{ categories { id } }\"}";

        System.Console.WriteLine("RAB: json: " + json);

        Newtonsoft.Json.Linq.JContainer postBody = (Newtonsoft.Json.Linq.JContainer)Newtonsoft.Json.JsonConvert.DeserializeObject(json);

        _reqMessage.Content = new StringContent(postBody.ToString(Formatting.None, new RestClient.MicrosoftJsonConverter()), Encoding.UTF8, "application/json");

        string token = "<insert your token>";

​

        httpClient.BaseAddress = new Uri("https://octopart.com/api/v4/endpoint?token=" + token);

        httpClient.DefaultRequestHeaders.ConnectionClose = true;

        var mess = _reqMessage.ToString();

        System.Console.WriteLine("RAB: message: " + mess);

        var resulta = httpClient.SendAsync(_reqMessage).GetAwaiter().GetResult();

        var reta = resulta.Content.ReadAsStringAsync().GetAwaiter().GetResult();

        Console.WriteLine(reta);

    }

}