using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Runtime.Serialization.Formatters;

using System.IO;

using System.Data;

using System.ComponentModel.DataAnnotations;

using System.Globalization;

​

​

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

using Newtonsoft.Json.Converters;

using Newtonsoft.Json.Serialization;    

​

    // https://stackoverflow.com/questions/47866386/newtonsoft-jsonconverter-access-other-properties

​

​

    [System.AttributeUsage(System.AttributeTargets.Property | System.AttributeTargets.Field, AllowMultiple = false)]

    public class JsonFormatAttribute : System.Attribute

    {

        public JsonFormatAttribute(string formattingString)

        {

            this.FormattingString = formattingString;

        }

​

        /// <summary>

        /// The format string to pass to string.Format()

        /// </summary>

        public string FormattingString { get; set; }

​

        /// <summary>

        /// The name of the underlying property that returns the object's culture, or NULL if not applicable.

        /// </summary>

        public string CulturePropertyName { get; set; }

    }

​

    public class FormattedPropertyContractResolver : DefaultContractResolver

    {

        protected override IList<JsonProperty> CreateProperties(Type type, MemberSerialization memberSerialization)

        {

            return base.CreateProperties(type, memberSerialization)

                .AddFormatting();

        }

    }

​

    public static class JsonContractExtensions

    {

        class FormattedValueProvider : IValueProvider

        {

            readonly IValueProvider baseProvider;

            readonly string formatString;

            readonly IValueProvider cultureValueProvider;

​

            public FormattedValueProvider(IValueProvider baseProvider, string formatString, IValueProvider cultureValueProvider)

            {

                this.baseProvider = baseProvider;

                this.formatString = formatString;

                this.cultureValueProvider = cultureValueProvider;

            }

​

            #region IValueProvider Members

​

            public object GetValue(object target)

            {

                var value = baseProvider.GetValue(target);

                var culture = cultureValueProvider == null ? null : (CultureInfo)cultureValueProvider.GetValue(target);

                return string.Format(culture ?? CultureInfo.InvariantCulture, formatString, value);

            }

​

            public void SetValue(object target, object value)

            {

                // This contract resolver should only be used for serialization, not deserialization, so throw an exception.

                throw new NotImplementedException();

            }

​

            #endregion

        }

​

        public static IList<JsonProperty> AddFormatting(this IList<JsonProperty> properties)

        {

            ILookup<string, JsonProperty> lookup = null;

​

            foreach (var jsonProperty in properties)

            {

                var attr = (JsonFormatAttribute)jsonProperty.AttributeProvider.GetAttributes(typeof(JsonFormatAttribute), false).SingleOrDefault();

                if (attr != null)

                {

                    IValueProvider cultureValueProvider = null;

                    if (attr.CulturePropertyName != null)

                    {

                        if (lookup == null)

                            lookup = properties.ToLookup(p => p.UnderlyingName);

                        var cultureProperty = lookup[attr.CulturePropertyName].FirstOrDefault();

                        if (cultureProperty != null)

                            cultureValueProvider = cultureProperty.ValueProvider;

                    }

                    jsonProperty.ValueProvider = new FormattedValueProvider(jsonProperty.ValueProvider, attr.FormattingString, cultureValueProvider);

                    jsonProperty.PropertyType = typeof(string);

                }

            }

            return properties;

        }

    }

​

    public class RootObject

    {

        [JsonFormat("{0:c}", CulturePropertyName = "Culture")]

        public decimal Cost { get; set; }

​

        [JsonIgnore]

        public CultureInfo Culture { get; set; }

​

        public string SomeValue { get; set; }

​

        public string SomeOtherValue { get; set; }

    }

​

    class TestClass

    {

        public static void Test()

        {

            var root = new RootObject

            {

                Cost = 101010101.23232m,

                Culture = new CultureInfo("de-DE"),

                SomeValue = "some value",

                SomeOtherValue = "some other value",

            };

​

            var settings = new JsonSerializerSettings

            {

                ContractResolver = new FormattedPropertyContractResolver

                {

                    //NamingStrategy = new CamelCaseNamingStrategy(),

                },

            };

            var json = JsonConvert.SerializeObject(root, Formatting.Indented, settings);

            Console.WriteLine(json);

        }

    }

​

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: " + Environment.Version);

            Console.WriteLine("Json.NET version: " + typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

                Console.WriteLine("Failed with unhandled exception: ");

                Console.WriteLine(ex);

                throw;

            }

        }

    }

​

    public class AssertionFailedException : System.Exception

    {

        public AssertionFailedException() : base() { }

​

        public AssertionFailedException(string s) : base(s) { }

    }

​

    public static class Assert

    {

        public static void IsTrue(bool value)

        {

            IsTrue(value, "failed");

        }

​

        public static void IsTrue(bool value, string message)

        {

            if (value == false)

                throw new AssertionFailedException(message ?? "failed");

        }

    }

​