解决雪花Id获取时精度丢失问题

这里拿.Net Core 6 来做演示

在Program.cs中加入如下代码:

builder.Services.AddControllersWithViews().AddNewtonsoftJson(options =>
{
   //循环引用
   options.SerializerSettings.ReferenceLoopHandling=Newtonsoft.Json.ReferenceLoopHandling.Ignore;
   //空值处理
   options.SerializerSettings.NullValueHandling=Newtonsoft.Json.NullValueHandling.Ignore;
   //大小写、处理雪花Id精度丢失
   options.SerializerSettings.ContractResolver = new CustomContractResolver();
   //修改时间的序列化方式
   options.SerializerSettings.Converters.Add(new IsoDateTimeConverter() { DateTimeFormat = "yyyy/MM/dd HH:mm:ss" });
});

代码中的CustomContractResolver是单独写了一个帮助类,作用是对长整形数据做处理具体代码如下:

public class CustomContractResolver : DefaultContractResolver
{
      /// <summary>
      /// 对长整型做处理
      /// </summary>
      /// <param name="objectType"></param>
      /// <returns></returns>
      protected override JsonConverter ResolveContractConverter(Type objectType)
      {
          if (objectType == typeof(long))
          {
              return new JsonConverterLong();
          }
          return base.ResolveContractConverter(objectType);
      }
}

自己创建一个名为CustomContractResolver类然后输入上面的代码。

最后在CustomContractResolver.cs中还有一个JsonConverterLong，这也是一个需要单独去创建的一个类需要去做处理代码如下：

public class JsonConverterLong : JsonConverter
    {
        /// <summary>
        /// 是否可以转换
        /// </summary>
        /// <param name="objectType"></param>
        /// <returns></returns>
        public override bool CanConvert(Type objectType)
        {
            return true;
        }

        /// <summary>
        /// 读json
        /// </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)
        {
            if ((reader.ValueType == null || reader.ValueType == typeof(long?)) && reader.Value == null)
            {
                return null;
            }
            else
            {
                long.TryParse(reader.Value != null ? reader.Value.ToString() : "", out long value);
                return value;
            }
        }

        /// <summary>
        /// 写json
        /// </summary>
        /// <param name="writer"></param>
        /// <param name="value"></param>
        /// <param name="serializer"></param>
        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
        {
            if (value == null)
                writer.WriteValue(value);
            else
                writer.WriteValue(value + "");
        }
    }