C# 对象与JSON字符串互相转换的三种方式

C# 对象与JSON字符串互相转换的三种方式

JSON(JavaScript Object Notation, JS 对象标记) 是一种轻量级的数据交换格式。

　　关于内存对象和JSON字符串的相互转换，在实际项目中应比较广泛，经过一番搜索，找到如下三种方法来解决此问题

分别是使用 Newtonsoft.Json.dll、DataContractJsonSerializer、 JavaScriptSerializer。

方法一： Newtonsoft.Json.dll

Newtonsoft.Json.dll在.net2.0之后的版本可以支持 我的版本.net framework4.0

添加Newtonsoft.json的引用

对象与json字符串转换类设计

     class JsonNewtonsoft
     {
         /// <summary>
         /// 把对象转换为JSON字符串
         /// </summary>
         /// <param name="o">对象</param>
         /// <returns>JSON字符串</returns>
         public static string ToJSON(this object o)
         {
             if (o == null)
             {
                 return null;
             }
             return JsonConvert.SerializeObject(o);
         }
         /// <summary>
         /// 把Json文本转为实体
         /// </summary>
         /// <typeparam name="T"></typeparam>
         /// <param name="input"></param>
         /// <returns></returns>
         public static T FromJSON<T>(this string input)
         {
             try
             {
                 return JsonConvert.DeserializeObject<T>(input);
             }
             catch (Exception ex)
             {
                 return default(T);
             }
         }
     }

方法二：DataContractJsonSerializer

使用这种 需要引用 System.Runtime.Serialization.dll

类设计

 class JsonDataContractJsonSerializer
     {
         /// <summary>
         /// 内存对象转换为json字符串
         /// </summary>
         /// <param name="obj"></param>
         /// <returns></returns>
         public static string ObjectToJson(object obj)
         {
            DataContractJsonSerializer serializer = new DataContractJsonSerializer(obj.GetType());
            MemoryStream stream = new MemoryStream();
            serializer.WriteObject(stream, obj);
            byte[] dataBytes = new byte[stream.Length];
            stream.Position = ;
            stream.Read(dataBytes, , (int)stream.Length);
            return Encoding.UTF8.GetString(dataBytes);
         }
        /// <summary>
        /// Json字符串转内存对象
        /// </summary>
        /// <param name="jsonString"></param>
        /// <param name="obj"></param>
        /// <returns></returns>
         public static object JsonToObject(string jsonString, object obj)
         {
            DataContractJsonSerializer serializer = new DataContractJsonSerializer(obj.GetType());
            MemoryStream mStream = new MemoryStream(Encoding.UTF8.GetBytes(jsonString));
            return serializer.ReadObject(mStream);
         }
     }

方法三：JavaScriptSerializer

需要引用：System.Web.Extensions.dll

类设计

     public static class JsonJavaScriptSerializer
     {
         /// <summary>
         /// 内存对象转换为json字符串
         /// </summary>
         /// <param name="obj"></param>
         /// <returns></returns>
         public static string ToJSON(object obj)
         {
             StringBuilder sb = new StringBuilder();
             JavaScriptSerializer json = new JavaScriptSerializer();
             json.Serialize(obj, sb);
             return sb.ToString();
         }
         /// <summary>
         /// Json字符串转内存对象
         /// </summary>
         /// <param name="jsonString"></param>
         /// <param name="obj"></param>
         /// <returns></returns>
         public static T FromJSON<T>(string jsonString)
         {
             JavaScriptSerializer json = new JavaScriptSerializer();
             return json.Deserialize<T>(jsonString);
         }

     }

程序测试：

新建一个测试对象类Student.cs

     public enum Sex
     {
         男=,
         女=
     }
     [Serializable()]
     class Student
     {
         private string _name;

         public string Name
         {
             get { return _name; }
             set { _name = value; }
         }

         private int _age;

         public int Age
         {
             get { return _age; }
             set { _age = value; }
         }

         private Sex _sex = Sex.男;

         public Sex Sex
         {
             get { return _sex; }
             set { _sex = value; }
         }
         public Student()
         { }
         public Student(string name,int age,Sex sex)
         {
             this._name = name;
             this._age = age;
             this._sex = sex;
         }
     }

测试程序

         static void Main(string[] args)
         {
             Student st = new Student("笨男孩",,Sex.男);

             Console.WriteLine("============方法一============================================");
             //方法一

             Console.WriteLine("方法一对象转Json字符串");
             string jsonStr = JsonNewtonsoft.ToJSON(st);
             Console.WriteLine(jsonStr);
             Console.WriteLine("方法一Json字符串转对象");
             Student stobj = (Student)JsonNewtonsoft.FromJSON<Student>(jsonStr);
             Console.WriteLine("姓名:{0} 年龄:{1} 性别:{2}",stobj.Name,stobj.Age,stobj.Sex);

             Console.WriteLine("============方法二============================================");
             //方法二
             Console.WriteLine("方法二对象转Json字符串");
             string jsonStr2 = JsonDataContractJsonSerializer.ToJSON(st);
             Console.WriteLine(jsonStr2);
             Console.WriteLine("方法二Json字符串转对象");
             Student stobj2 = (Student)JsonDataContractJsonSerializer.FromJSON(jsonStr2, st);
             Console.WriteLine("姓名:{0} 年龄:{1} 性别:{2}", stobj2.Name, stobj2.Age, stobj2.Sex);

             Console.WriteLine("============方法三============================================");
             //方法二
             Console.WriteLine("方法三对象转Json字符串");
             string jsonStr3 = JsonJavaScriptSerializer.ToJSON(st);
             Console.WriteLine(jsonStr3);
             Console.WriteLine("方法三Json字符串转对象");
             Student stobj3 = (Student)JsonJavaScriptSerializer.FromJSON<Student>(jsonStr3);
             Console.WriteLine("姓名:{0} 年龄:{1} 性别:{2}", stobj3.Name, stobj3.Age, stobj3.Sex);

             Console.ReadKey();
         }

程序运行结果：

运行结果：

 程序工程源文件下载

功能对比：

性能对比：

综上所述，一般采用Json.NET方法一比较好！

参考：

JavaScriptSerializer 类介绍 https://msdn.microsoft.com/zh-cn/library/system.web.script.serialization.javascriptserializer(v=vs.110).aspx

DataContractJsonSerializer类介绍 https://msdn.microsoft.com/zh-cn/library/system.runtime.serialization.json.datacontractjsonserializer(v=vs.110).aspx

https://blog.csdn.net/testcs_dn/article/details/78150046?locationNum=6&fps=1