需求:long類型的值大於9007199254740991值時,前端會失精度,由於表結構ID用的long類型,修改程序字段類型不現實,網管統一處理,將long類型大於9007199254740991值時改為sting類型
方案:
public class CustomContractResolver : DefaultContractResolver { /// <summary> /// 對長整型做處理 /// </summary> /// <param name="objectType"></param> /// <returns></returns> protected override JsonConverter ResolveContractConverter(Type objectType) { if (objectType == typeof(long)) { return new JsonConverterLong(); } return base.ResolveContractConverter(objectType); } }
public class JsonConverterLong : JsonConverter {
public override bool CanRead => false; /// <summary> /// 是否可以轉換 /// </summary> /// <param name="objectType"></param> /// <returns></returns> public override bool CanConvert(Type objectType) { return true; } /// <summary> /// 讀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) { //此方法不會進來,因為設置的上面CanRead是false return reader.Value; } /// <summary> /// 寫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 || Convert.ToInt64(value) < 9007199254740991) writer.WriteValue(value); else writer.WriteValue(value + ""); } }
參考:
https://www.cnblogs.com/yijiayi/p/10051284.html
https://www.cnblogs.com/binbinxu/p/13061561.html