Newtonsoft.Json 自定义转换器 ——特定数据类型序列化失败完美解决方案

场景

最近在做一个关于OPC项目，项目中把对象序列化成Json,使用了Newtonsoft.Json插件，当序列化byte数组时，发现byte[] 被序列化成一个字符串，在浏览官方文档时，发现可以针对特定类型写相应的转换器。

解决方案

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Newtonsoft.Json;

namespace ConsoleApp2
{
    internal class Program
    {
        private static void Main(string[] args)
        {
            var data = new Demo {Data = new byte[] {1, 3, 4}};
            var error = JsonConvert.SerializeObject(data);
            Console.Write("error json:");
            ShowError(error);
            Console.WriteLine();
            var setting = new JsonSerializerSettings
            {
                Converters = new List<JsonConverter>
                {
                    new JsonByteArrayConverter()
                }
            };
            var json = JsonConvert.SerializeObject(data, setting);
            Console.WriteLine($"correct json:{json}");
            Console.ReadKey();
        }

        private static void ShowError(string input)
        {
            Console.ForegroundColor = ConsoleColor.Red;
            Console.Write(input);
            Console.ForegroundColor = ConsoleColor.White;
        }
    }

    internal class Demo
    {
        [JsonProperty("data")]
        public byte[] Data { get; set; }
    }

    public class JsonByteArrayConverter : JsonConverter
    {
        /// <summary>
        ///     写入Json数据
        /// </summary>
        /// <param name="writer"></param>
        /// <param name="value"></param>
        /// <param name="serializer"></param>
        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
        {
            var result = new StringBuilder();
            if (value is byte[] temp)
                foreach (var item in temp)
                    result.AppendFormat("{0},", item);
            writer.WriteValue($"[{result.ToString().Trim(',')}]");
        }

        /// <summary>
        ///     读Json数据
        /// </summary>
        /// <param name="reader"></param>
        /// <param name="objectType"></param>
        /// <param name="existingValue"></param>
        /// <param name="serializer"></param>
        /// <returns></returns>
        public override object ReadJson(JsonReader reader, Type objectType, object existingValue,
            JsonSerializer serializer)
        {
            var strValue = reader.Value.ToString();
            var temp = strValue.Split(',');
            return temp.Select(x => byte.Parse(x)).ToArray();
        }

        /// <summary>
        ///     是否可以转换
        /// </summary>
        /// <param name="objectType"></param>
        /// <returns></returns>
        public override bool CanConvert(Type objectType)
        {
            return objectType == typeof(byte[]);
        }
    }
}