using System;

using System.Collections.Generic;

using System.Linq;

​

using System.Text.Json;

​

class Program

{

    static void Main(string[] args)

    {

        string input = @"{

      ""key"": ""MobileNetworkOperator"",

      ""name"": ""MNO Option"",

      ""type"": ""n"",

      ""options"": [

        {

          ""0"": ""Spark LTE M1""

        },

        {

          ""1"": ""Default""

        },

        {

          ""2"": ""AT&T""

        },

        {

          ""3"": ""Verizon""

        },

        {

          ""4"": ""Telstra""

        },

        {

          ""5"": ""T-Mobile USA""

        },

        {

          ""6"": ""China Telecom""

        },

        {

          ""7"": ""Sprint""

        },

        {

          ""8"": ""Vodafone""

        },

        {

          ""9"": ""Telus""

        },

        {

          ""10"": ""Deutsche Telecom""

        },

        {

          ""11"": ""Standard Europe""

        }

      ],

      ""rebootRequired"": true,

      ""default"": 0

}";

        var jsonDto = JsonSerializer.Deserialize<JsonDto>(input);

        var result = new UsableObject {

                        Key=jsonDto.key,

                        Name=jsonDto.name,

                        Type=jsonDto.type,

                        RebootRequired=jsonDto.rebootRequired,

                        Default=jsonDto.@default,

                        Options=jsonDto.options

                                        .SelectMany(trd=> trd)

                                        .ToDictionary(kvp=> kvp.Key, kvp=> kvp.Value),

                     };

        result.Options.Dump();

    }

}

​

public partial class JsonDto

{

    public string key { get; set; }

    public string name { get; set; }

    public string type { get; set; }

    public List<Dictionary<string, string>> options { get; set; }

    public bool rebootRequired { get; set; }

    public long @default { get; set; }

}

​

public partial class UsableObject {

    public string Key { get; set; }

    public string Name { get; set; }

    public string Type { get; set; }

    public Dictionary<string, string> Options { get; set; }

    public bool RebootRequired { get; set; }

    public long Default { get; set; }

}

​