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.net中怎樣實現json轉化時僅僅處理部分屬性二?

add solver too 不能 track for dynamic returns sof



在第一篇文章中使用的json方法。能夠依照須要僅僅處理須要的屬性,但卻要求屬性不能是復雜的類型,比如泛型,數組。其它用戶自己定義的類等,限制太多,於是自己看看能不能改進,想不到Newtonsoft.Json提供有相關的接口,僅僅須要實現就能夠了。

僅僅須要繼承DefaultContractResolver,並改寫一個方法就能夠了。

核心代碼:

 /// <summary>
        /// 對象轉為json,全部屬性都輸出
        /// </summary>
        /// <typeparam name="ObjType"></typeparam>
        /// <param name="obj"></param>
        /// <returns></returns>
        public static string ObjToJsonString<ObjType>(ObjType obj) where ObjType : class
        {
            string s = JsonConvert.SerializeObject(obj);
            return s;
        }
        /// <summary>
        /// 對象轉為json,僅僅輸出部分屬性
        /// </summary>
        /// <typeparam name="T">對象類型</typeparam>
        /// <param name="t">對象類型值</param>
        /// <param name="propertyInfos">須要json處理的屬性名稱。以逗號分隔</param>
        /// <returns></returns>
        public static string ObjToJsonString<T>(T t, string propertyInfos) where T : class
        {
             string[] cols = propertyInfos.Split(new char[] { ‘,‘ }, StringSplitOptions.RemoveEmptyEntries);
             List<string> _propertyNames = new List<string>();
             foreach (string col in cols)
             {  
                 string   colTemp = col.ToLower().Trim();
                 if (!_propertyNames.Contains(colTemp))
                 {
                     _propertyNames.Add(colTemp);
                 }
             }
             string s = JsonConvert.SerializeObject(t, Formatting.Indented, new JsonSerializerSettings { ContractResolver = new DynamicContractResolver(_propertyNames) });
            return s;
        }
        /// <summary>
        /// json轉為對象
        /// </summary>
        /// <typeparam name="ObjType"></typeparam>
        /// <param name="JsonString"></param>
        /// <returns></returns>
        public static ObjType JsonStringToObj<ObjType>(string JsonString) where ObjType : class
        {          
            ObjType s = JsonConvert.DeserializeObject<ObjType>(JsonString);
            return s;
        }
        class DynamicContractResolver : DefaultContractResolver
        {

            private readonly List<string> _propertyNames;
            public DynamicContractResolver(List<string> propertyNames)
            {
                _propertyNames = propertyNames;
            }
            /// <summary>
            /// 假設屬性是對象。須要把這個對象的屬性也傳給propertyNames,
            /// 否則處理這個對象屬性時,就不包括相應的屬性值
            /// </summary>
            /// <param name="type"></param>
            /// <param name="memberSerialization"></param>
            /// <returns></returns>
            protected override IList<JsonProperty> CreateProperties(Type type, MemberSerialization memberSerialization)
            {
                IList<JsonProperty> properties = base.CreateProperties(type, memberSerialization);
                IList<JsonProperty> propertiesReturn = new List<JsonProperty>();//須要json處理的屬性
                foreach (JsonProperty item in properties)
                { 
                    
                     string PropertyNameTemp = item.PropertyName.ToLower().Trim();
                    if (_propertyNames.Contains(PropertyNameTemp))
                    {
                        propertiesReturn.Add(item);                   
                    }
                }

                return propertiesReturn;
            }
        }





.net中怎樣實現json轉化時僅僅處理部分屬性二?