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:

 
     
      
     
     
     namespace 
     SL_DataContractJsonSerializer
 {
  
     public 
      
     partial 
      
     class 
     Page:UserControl
 {
  
     public 
     Page()
 {
 InitializeComponent();
 }
 
  
     // 
     Thisusesaneventhandler,notSLdatabinding 
     
  
      
     void 
     OnClick( 
     object 
     sender,EventArgsargs)
 {
 txtOutput1.Text 
     = 
      
     " 
     CreateaUserobjectandserializeit. 
     " 
     ;
  
     string 
     json 
     = 
     WriteFromObject();
 txtOutput2.Text 
     = 
     json.ToString(); 
     Displays:{"Age":42,"Name":"Bob"} 
     
  
     
 txtOutput3.Text 
     = 
      
     DeserializethedatatoaUserobject. 
     string 
     jsonString 
     = 
      
     {'Name':'Bill','Age':53} 
     " 
     ;
 UserdeserializedUser 
     = 
     ReadToObject(jsonString);
 txtOutput4.Text 
     = 
     deserializedUser.Name; 
     Displays:Bill 
     
  
     txtOutput5.Text 
     = 
     deserializedUser.Age.ToString(); 
     Displays:53 
     
  
     }
  
     CreateaUserobjectandserializeittoaJSONstream. 
     static 
      
     string 
     WriteFromObject()
 {
  
     CreateUserobject. 
     
  
     Useruser 
     = 
      
     new 
     User( 
     Bob 
     " 
     , 
     42 
     );
 
  
     Createastreamtoserializetheobjectto. 
     
  
     MemoryStreamms 
     = 
      
     new 
     MemoryStream();
 
  
     SerializertheUserobjecttothestream. 
     
  
     DataContractJsonSerializerser 
     = 
      
     new 
     DataContractJsonSerializer( 
     typeof 
     (User));
 ser.WriteObject(ms,user);
  
     byte 
     []json 
     = 
     ms.ToArray();
 ms.Close();
  
     return 
     Encoding.UTF8.GetString(json,128); line-height:1.5!important">0 
     ,json.Length);
 
 }
 
  
     DeserializeaJSONstreamtoaUserobject. 
     static 
     UserReadToObject( 
     string 
     json)
 {
 UserdeserializedUser 
     = 
      
     new 
     User();
 MemoryStreamms 
     = 
      
     new 
     MemoryStream(Encoding.UTF8.GetBytes(json));
 DataContractJsonSerializerser 
     = 
      
     new 
     DataContractJsonSerializer(deserializedUser.GetType());
 deserializedUser 
     = 
     ser.ReadObject(ms) 
     as 
     User;
 ms.Close();
  
     return 
     deserializedUser;
 }
 
 }
 
 [DataContract]
  
     class 
     User
 {
 [DataMember]
  
     string 
     Name{ 
     get 
     ; 
     set 
     ;}
 
 [DataMember]
  
     int 
     Age{ 
     set 
     ;}
 
  
     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> 
    <typeparamname="T"></typeparam> 
    <paramname="obj"></param> 
    <returns></returns> 
    
  
     
    static 
     
    string 
    GetJson 
    < 
    T 
    > 
    (Tobj)
 {
 DataContractJsonSerializerjson 
    = 
     
    new 
    DataContractJsonSerializer(obj.GetType());
  
    using 
    (MemoryStreamstream 
    = 
     
    new 
    MemoryStream())
 {
 json.WriteObject(stream,obj);
  
    string 
    szJson 
    = 
    Encoding.UTF8.GetString(stream.ToArray());
  
    return 
    szJson;
 }
 }
  
    获取Json的Model
  
    <paramname="szJson"></param> 
    static 
    TParseFromJson 
    < 
    T 
    > 
    ( 
    string 
    szJson)
 {
 Tobj 
    = 
    Activator.CreateInstance 
    < 
    T 
    > 
    ();
  
    using 
    (MemoryStreamms 
    = 
     
    new 
    MemoryStream(Encoding.UTF8.GetBytes(szJson)))
 {
 DataContractJsonSerializerserializer 
    = 
     
    return 
    (T)serializer.ReadObject(ms);
 }
 }
 } 
   

 
     
    反回JSON数据到前台
  
    <paramname="dt"> 
    数据表 
    </param> 
    <returns> 
    JSON字符串 
    </returns> 
    string 
    DataTableToJson(DataTabledt)
 {
 StringBuilderJsonString 
    = 
     
    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( 
    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 
    - 
     
    "" 
    );
 }
 }
  
    if 
    (i 
    == 
    dt.Rows.Count 
    - 
     
    } 
    else 
    
 {
 JsonString.Append( 
    },0); line-height:1.5!important">" 
    );
 }
 }
 JsonString.Append( 
    ]} 
    return 
    JsonString.ToString();
 }
  
    else 
    
 {
  
    return 
     
    null 
    ;
 }
 } 
   

//还有一种方式操作json类型数据:

 
    class 
    JsonTableHelper
 {
  
    返回对象序列化
  
    <paramname="obj"> 
    源对象 
    json数据 
    </returns> 
    string 
    ToJson( 
    this 
     
    object 
    obj)
 {
 JavaScriptSerializerserialize 
    = 
     
    new 
    JavaScriptSerializer();
  
    return 
    serialize.Serialize(obj);
 }
 
  
    控制深度
  
    <paramname="recursionDepth"> 
    深度 
    object 
    obj, 
    int 
    recursionDepth)
 {
 JavaScriptSerializerserialize 
    = 
     
    new 
    JavaScriptSerializer();
 serialize.RecursionLimit 
    = 
    recursionDepth;
  
    DataTable转为json
  
    DataTable 
    string 
    ToJson(DataTabledt)
 {
 Dictionary 
    < 
    string 
    ,255); line-height:1.5!important">object 
    > 
    dic 
    = 
     
    new 
    Dictionary 
    < 
    object 
    > 
    ();
 
  
    int 
    index 
    = 
     
    0 
    ;
  
    foreach 
    (DataRowdr 
    in 
    dt.Rows)
 {
 Dictionary 
    < 
    object 
    > 
    result 
    = 
     
    foreach 
    (DataColumndc 
    in 
    dt.Columns)
 {
 result.Add(dc.ColumnName,dr[dc].ToString());
 }
 dic.Add(index.ToString(),result);
 index 
    ++ 
    ;
 }
  
    return 
    ToJson(dic);
 }
 }