using System;

using System.Collections.Generic;

using System.Linq;

using Newtonsoft.Json.Linq;

public class Program

{

    public static void Main()

    {

        string json = @"

              [

                {

                  ""expand"": ""html"",

                  ""id"": ""10230"",

                  ""self"": ""http://localhost:8080/rest/api/2/issue/BULK-62"",

                  ""key"": ""BULK-62"",

                  ""fields"": {

                    ""summary"": ""testing"",

                    ""timetracking"": null,

                    ""issuetype"": {

                      ""self"": ""http://localhost:8080/rest/api/2/issuetype/5"",

                      ""id"": ""5"",

                      ""description"": ""The sub-task of the issue"",

                      ""iconUrl"": ""http://localhost:8080/images/icons/issue_subtask.gif"",

                      ""name"": ""Sub-task"",

                      ""subtask"": true

                    },

                    ""customfield_10071"": null

                  },

                  ""transitions"": ""http://localhost:8080/rest/api/2/issue/BULK-62/transitions""

                },

                {

                  ""expand"": ""html"",

                  ""id"": ""10004"",

                  ""self"": ""http://localhost:8080/rest/api/2/issue/BULK-47"",

                  ""key"": ""BULK-47"",

                  ""fields"": {

                    ""summary"": ""Cheese v1 2.0 issue"",

                    ""timetracking"": null,

                    ""issuetype"": {

                      ""self"": ""http://localhost:8080/rest/api/2/issuetype/3"",

                      ""id"": ""3"",

                      ""description"": ""A task that needs to be done."",

                      ""iconUrl"": ""http://localhost:8080/images/icons/task.gif"",

                      ""name"": ""Task"",

                      ""subtask"": false

                    }

                  },

                  ""transitions"": ""http://localhost:8080/rest/api/2/issue/BULK-47/transitions""

                }

              ]";

​

        var columnPathMappings = new Dictionary<string, string>

        {

            { "key", "key" },

            { "summary", "fields.summary" },

            { "issue type", "fields.issuetype.name" },

        };

​

        string csv = JArray.Parse(json).Cast<JObject>().ToCsv(columnPathMappings);

​

        Console.WriteLine(csv);

    }

}

​

public static class JsonHelper

{

    public static string ToCsv(this IEnumerable<JObject> items, Dictionary<string, string> columnPathMappings)

    {

        if (items == null || columnPathMappings == null) 

            throw new ArgumentNullException();

​

        var rows = new List<string>();

        rows.Add(columnPathMappings.Keys.ToCsv());

        foreach (JObject item in items)

        {

            rows.Add(columnPathMappings.Values.Select(path => item.SelectToken(path)).ToCsv());

        }

        return string.Join(Environment.NewLine, rows);

    }

​

    public static string ToCsv(this IEnumerable<object> values)

    {

        const string quote = "\"";

        const string doubleQuote = "\"\"";

        return string.Join(",", values.Select(v => v != null ? string.Concat(quote, v.ToString().Replace(quote, doubleQuote), quote) : string.Empty));

    }

}