环境说明
服务端有个接口，返回json格式的数据，要求输出数据的字段由客户端决定。
测试样例
using Newtonsoft.Json;using System;namespace Hitearth{ ???class Hitearth ???{ ???????static void Main(string[] args) ???????{ ???????????var demos = new[] ???????????{ ???????????????new demo { attr1 = "11", attr2 = "12",attr3 = "13" }, ???????????????new demo { attr1 = "21", attr2 = "22",attr3 = "23" }, ???????????}; ???????????var demo2 = new demo(); ???????????demo2.obj = demo2; ???????????var demo3 = new demo { attr2 = "demo3" }; ???????????demo3.obj = new demo { attr2 = "demo3.obj", obj = new demo { attr2 = "demo3.obj.obj" } }; ???????????Console.WriteLine(JsonConvert.SerializeObject(demos)); ?// [{"attr1":"11","attr2":"12","attr3":"13","obj":null},{"attr1":"21","attr2":"22","attr3":"23","obj":null}] ???????????test(demos, "attr1 attr2".Split(‘ ‘)); // [{"attr1":"11","attr2":"12"},{"attr1":"21","attr2":"22"}] ???????????test(demos, "attr2 attr3".Split(‘ ‘)); // [{"attr2":"12","attr3":"13"},{"attr2":"22","attr3":"23"}] ???????????test(demos, new string[] { }); // [{},{}] ???????????test(demo2, "attr2 attr3".Split(‘ ‘)); ?// {"attr2":null,"attr3":null} ???????????test(demo2, "attr2 obj".Split(‘ ‘)); ?// Self referencing loop detected with type ‘Hitearth.demo‘.Path ‘‘. ???????????test(demo3, "attr2 obj".Split(‘ ‘));// {"attr2":"demo3","obj":{"attr2":"demo3.obj","obj":{"attr2":"demo3.obj.obj","obj":null}}} ???????} ???????static void test(object obj, string[] attrs) ???????{ ???????????try ???????????{ ???????????????Console.WriteLine(JsonConvert.SerializeObject(obj, new FilterPropertiesJsonConverter(typeof(demo), attrs))); ???????????} ???????????catch (Exception ex) ???????????{ ???????????????Console.WriteLine(ex.Message); ???????????} ???????} ???} ???public class demo ???{ ???????public string attr1 { get; set; } ???????public string attr2 { get; set; } ???????public string attr3 { get; set; } ???????public demo obj { get; set; } ???}}
using Newtonsoft.Json;using Newtonsoft.Json.Serialization;using System;using System.Linq;namespace Hitearth{ ???/// <summary> ???/// 只序列化 jsonProperties 指定的字段 ???/// </summary> ???/// <typeparam name="T"></typeparam> ???public class FilterPropertiesJsonConverter : JsonConverter ???{ ???????Type type; string[] jsonProperties; bool reversed = false; ???????public FilterPropertiesJsonConverter(Type type, string[] jsonProperties, bool reversed = false) ???????{ ???????????if (type == null) throw new ArgumentNullException("type"); ???????????if (jsonProperties == null) throw new ArgumentNullException("jsonProperties"); ???????????this.type = type; ???????????this.jsonProperties = jsonProperties; ???????????this.reversed = reversed; ???????} ???????public override bool CanConvert(Type objectType) ???????{ ???????????return objectType == type; ???????} ???????public override bool CanRead { get { return false; } } ???????public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer) { throw new NotImplementedException(); } ???????public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer) ???????{ ???????????if (value == null) ???????????{ ???????????????writer.WriteNull(); ???????????????return; ???????????} ???????????var contract = serializer.ContractResolver.ResolveContract(value.GetType()) as JsonObjectContract; ???????????writer.WriteStartObject(); ???????????if (contract != null) ???????????{ ???????????????foreach (var item in contract.Properties) ???????????????{ ???????????????????if (jsonProperties.Contains(item.PropertyName) == reversed) ???????????????????????continue; ???????????????????writer.WritePropertyName(item.PropertyName); ???????????????????serializer.Serialize(writer, item.ValueProvider.GetValue(value)); ???????????????} ???????????} ???????????writer.WriteEndObject(); ???????} ???}}Json.net 动态序列化属性
原文地址：https://www.cnblogs.com/hitearth/p/10323186.html