• DataContractJsonSerializer 类 操作json类型数据


    将对象序列化为 JavaScript 对象表示法 (JSON),并将 JSON 数据反序列化为对象。 此类不能继承。

    //  msdn 例子:

    代码
    namespace SL_DataContractJsonSerializer
    {
        
    public partial class Page : UserControl
        {
            
    public Page()
            {
                InitializeComponent();
            }

            
    //This uses an event handler, not SL data binding
            void OnClick(object sender, EventArgs args)
            {
                txtOutput1.Text 
    = "Create a User object and serialize it.";
                
    string json = WriteFromObject();
                txtOutput2.Text 
    = json.ToString(); // Displays: {"Age":42,"Name":"Bob"}

                txtOutput3.Text 
    = "Deserialize the data to a User object.";
                
    string jsonString = "{'Name':'Bill', 'Age':53}";
                User deserializedUser 
    = ReadToObject(jsonString);
                txtOutput4.Text 
    = deserializedUser.Name; // Displays: Bill
                txtOutput5.Text = deserializedUser.Age.ToString(); // Displays: 53
            }
            
    // Create a User object and serialize it to a JSON stream.
            public static string WriteFromObject()
            {
                
    //Create User object.
                User user = new User("Bob"42);

                
    //Create a stream to serialize the object to.
                MemoryStream ms = new MemoryStream();

                
    // Serializer the User object to the stream.
                DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(User));
                ser.WriteObject(ms, user);
                
    byte[] json = ms.ToArray();
                ms.Close();
                
    return Encoding.UTF8.GetString(json, 0, json.Length);

            }

            
    // Deserialize a JSON stream to a User object.
            public static User ReadToObject(string json)
            {
                User deserializedUser 
    = new User();
                MemoryStream ms 
    = new MemoryStream(Encoding.UTF8.GetBytes(json));
                DataContractJsonSerializer ser 
    = new DataContractJsonSerializer(deserializedUser.GetType());
                deserializedUser 
    = ser.ReadObject(ms) as User;
                ms.Close();
                
    return deserializedUser;
            }

        }

        [DataContract]
        
    public class User
        {
            [DataMember]
            
    public string Name { getset; }

            [DataMember]
            
    public int Age { getset; }

            
    public User() { }

            
    public User(string newName, int newAge)
            {
                Name 
    = newName;
                Age 
    = newAge;
            }

        }

    }


     可以抽象成如下类:

     public class JsonHelper
        {
            
    /// <summary>
            
    /// 生成Json格式
            
    /// </summary>
            
    /// <typeparam name="T"></typeparam>
            
    /// <param name="obj"></param>
            
    /// <returns></returns>
            public static string GetJson<T>(T obj)
            {
                DataContractJsonSerializer json 
    = new DataContractJsonSerializer(obj.GetType());
                
    using (MemoryStream stream = new MemoryStream())
                {
                    json.WriteObject(stream, obj);
                    
    string szJson = Encoding.UTF8.GetString(stream.ToArray()); 
                    
    return szJson;
                }
            }
            
    /// <summary>
            
    /// 获取Json的Model
            
    /// </summary>
            
    /// <typeparam name="T"></typeparam>
            
    /// <param name="szJson"></param>
            
    /// <returns></returns>
            public static T ParseFromJson<T>(string szJson)
            {
                T obj 
    = Activator.CreateInstance<T>();
                
    using (MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(szJson)))
                {
                    DataContractJsonSerializer serializer 
    = new DataContractJsonSerializer(obj.GetType());
                    
    return (T)serializer.ReadObject(ms);
                }
            }
        }
            /// <summary>
            
    /// 反回JSON数据到前台
            
    /// </summary>
            
    /// <param name="dt">数据表</param>
            
    /// <returns>JSON字符串</returns>
            public string DataTableToJson(DataTable dt)
            {
                StringBuilder JsonString 
    = new StringBuilder();
                
    if (dt != null && dt.Rows.Count > 0)
                {
                    JsonString.Append(
    "");
                    JsonString.Append(
    "\"TableInfo\":[ ");
                    
    for (int i = 0; i < dt.Rows.Count; i++)
                    {
                        JsonString.Append(
    "");
                        
    for (int j = 0; j < dt.Columns.Count; j++)
                        {
                            
    if (j < dt.Columns.Count - 1)
                            {
                                JsonString.Append(
    "\"" + dt.Columns[j].ColumnName.ToString() + "\":" + "\"" + dt.Rows[i][j].ToString() + "\",");
                            }
                            
    else if (j == dt.Columns.Count - 1)
                            {
                                JsonString.Append(
    "\"" + dt.Columns[j].ColumnName.ToString() + "\":" + "\"" + dt.Rows[i][j].ToString() + "\"");
                            }
                        }
                        
    if (i == dt.Rows.Count - 1)
                        {
                            JsonString.Append(
    "");
                        }
                        
    else
                        {
                            JsonString.Append(
    "}, ");
                        }
                    }
                    JsonString.Append(
    "]}");
                    
    return JsonString.ToString();
                }
                
    else
                {
                    
    return null;
                }
            }

    //还有一种方式操作json类型数据:

    public static class JsonTableHelper
        {
            
    /// <summary> 
            
    /// 返回对象序列化 
            
    /// </summary> 
            
    /// <param name="obj">源对象</param> 
            
    /// <returns>json数据</returns> 
            public static string ToJson(this object obj)
            {
                JavaScriptSerializer serialize 
    = new JavaScriptSerializer();
                
    return serialize.Serialize(obj);
            }

            
    /// <summary> 
            
    /// 控制深度 
            
    /// </summary> 
            
    /// <param name="obj">源对象</param> 
            
    /// <param name="recursionDepth">深度</param> 
            
    /// <returns>json数据</returns> 
            public static string ToJson(this object obj, int recursionDepth)
            {
                JavaScriptSerializer serialize 
    = new JavaScriptSerializer();
                serialize.RecursionLimit 
    = recursionDepth;
                
    return serialize.Serialize(obj);
            }

            
    /// <summary> 
            
    /// DataTable转为json 
            
    /// </summary> 
            
    /// <param name="dt">DataTable</param> 
            
    /// <returns>json数据</returns> 
            public static string ToJson(DataTable dt)
            {
                Dictionary
    <stringobject> dic = new Dictionary<stringobject>();

                
    int index = 0;
                
    foreach (DataRow dr in dt.Rows)
                {
                    Dictionary
    <stringobject> result = new Dictionary<stringobject>();

                    
    foreach (DataColumn dc in dt.Columns)
                    {
                        result.Add(dc.ColumnName, dr[dc].ToString());
                    }
                    dic.Add(index.ToString(), result);
                    index
    ++;
                }
                
    return ToJson(dic);
            }
        }


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  • 原文地址:https://www.cnblogs.com/chenqingwei/p/1754522.html
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