我有一个简单的JSON键/值列表,通过POST发送回ASP.NET。例子:

{ "key1": "value1", "key2": "value2"}

我没有试图反序列化为强类型的.NET对象

我只需要一个普通的旧字典(Of String,String),或者一些等价的东西(哈希表,字典(OfString,Object),老式的StringDictionary——见鬼,一个二维字符串数组对我来说很有用。

我可以使用ASP.NET 3.5中可用的任何东西,也可以使用流行的Json.NET(我已经在使用它对客户端进行序列化)。

显然,这两个JSON库都没有这种开箱即用的能力——它们完全专注于通过强契约实现基于反射的反序列化。

有什么想法吗?

限制:

我不想实现我自己的JSON解析器尚无法使用ASP.NET 4.0希望远离旧的、不推荐使用的JSON ASP.NET类


当前回答

我建议使用.NET4.5中的System.Runtime.Serialization.Json。

[DataContract]
public class Foo
{
   [DataMember(Name = "data")]
   public Dictionary<string,string> Data { get; set; }
}

然后这样使用:

var serializer = new DataContractJsonSerializer(typeof(List<Foo>));
var jsonParams = @"{""data"": [{""Key"":""foo"",""Value"":""bar""}] }";
var stream = new MemoryStream(Encoding.UTF8.GetBytes(jsonParams));

var obj = serializer.ReadObject(stream);
Console.WriteLine(obj);

其他回答

我将JSON中的空值检查添加到另一个答案中

我也有同样的问题,所以我自己写了这个。此解决方案是与其他答案不同,因为它可以反序列化为多个级别。

只需将json字符串发送到反序列化ToDictionary函数将返回非强类型Dictionary<string,object>object。

private Dictionary<string, object> deserializeToDictionary(string jo)
{
    var values = JsonConvert.DeserializeObject<Dictionary<string, object>>(jo);
    var values2 = new Dictionary<string, object>();
    foreach (KeyValuePair<string, object> d in values)
    {
        if (d.Value != null && d.Value.GetType().FullName.Contains("Newtonsoft.Json.Linq.JObject"))
        {
            values2.Add(d.Key, deserializeToDictionary(d.Value.ToString()));
        }
        else
        {
            values2.Add(d.Key, d.Value);
        }
    }
    return values2;
}

示例:这将返回Facebook的Dictionary<string,object>objectJSON响应。

private void button1_Click(object sender, EventArgs e)
{
    string responsestring = "{\"id\":\"721055828\",\"name\":\"Dasun Sameera
        Weerasinghe\",\"first_name\":\"Dasun\",\"middle_name\":\"Sameera\",\"last_name\":\"Weerasinghe\",\"username\":\"dasun\",\"gender\":\"male\",\"locale\":\"en_US\",
        hometown: {id: \"108388329191258\", name: \"Moratuwa, Sri Lanka\",}}";
    Dictionary<string, object> values = deserializeToDictionary(responsestring);
}

注意:home进一步反序列化为Dictionary<string,object>对象。

游戏开始得有点晚了,但上面的解决方案中没有一个给我指明了一个纯粹而简单的.NET,而不是json.NET解决方案的方向。这就是,最后变得非常简单。下面是一个完整的运行示例,说明如何使用标准.NETJson序列化,该示例在根对象和子对象中都有字典。

关键是这只猫,将设置解析为序列化程序的第二个参数:

DataContractJsonSerializerSettings settings =
                       new DataContractJsonSerializerSettings();
                    settings.UseSimpleDictionaryFormat = true;

完整代码如下:

using System;
using System.Collections.Generic;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Json;

    namespace Kipon.dk
    {
        public class JsonTest
        {
            public const string EXAMPLE = @"{
                ""id"": ""some id"",
                ""children"": {
                ""f1"": {
                    ""name"": ""name 1"",
                    ""subs"": {
                    ""1"": { ""name"": ""first sub"" },
                    ""2"": { ""name"": ""second sub"" }
                    }
                },
                ""f2"": {
                    ""name"": ""name 2"",
                    ""subs"": {
                    ""37"": { ""name"":  ""is 37 in key""}
                    }
                }
                }
            }
            ";

            [DataContract]
            public class Root
            {
                [DataMember(Name ="id")]
                public string Id { get; set; }

                [DataMember(Name = "children")]
                public Dictionary<string,Child> Children { get; set; }
            }

            [DataContract]
            public class Child
            {
                [DataMember(Name = "name")]
                public string Name { get; set; }

                [DataMember(Name = "subs")]
                public Dictionary<int, Sub> Subs { get; set; }
            }

            [DataContract]
            public class Sub
            {
                [DataMember(Name = "name")]
                public string Name { get; set; }
            }

            public static void Test()
            {
                var array = System.Text.Encoding.UTF8.GetBytes(EXAMPLE);
                using (var mem = new System.IO.MemoryStream(array))
                {
                    mem.Seek(0, System.IO.SeekOrigin.Begin);
                    DataContractJsonSerializerSettings settings =
                       new DataContractJsonSerializerSettings();
                    settings.UseSimpleDictionaryFormat = true;

                    var ser = new DataContractJsonSerializer(typeof(Root), settings);
                    var data = (Root)ser.ReadObject(mem);
                    Console.WriteLine(data.Id);
                    foreach (var childKey in data.Children.Keys)
                    {
                        var child = data.Children[childKey];
                        Console.WriteLine(" Child: " + childKey + " " + child.Name);
                        foreach (var subKey in child.Subs.Keys)
                        {
                            var sub = child.Subs[subKey];
                            Console.WriteLine("   Sub: " + subKey + " " + sub.Name);
                        }
                    }
                }
            }
        }
    }

似乎所有这些答案都是假设你可以从一个更大的物体中得到一个小字符串。。。对于那些希望简单地在映射中某个地方使用这样的字典来实现大型对象的人,以及使用System.Runtime.Serialization.Json DataContract系统的人,这里有一个解决方案:

gis.stackeexchange.com上的一个答案有这个有趣的链接。我不得不用archive.org恢复它,但它提供了一个非常完美的解决方案:一个自定义的IDataContractSurrogate类,您可以在其中完全实现自己的类型。我能够很容易地扩展它。

不过,我做了很多改变。由于原始源不再可用,我将在这里发布整个课程:

using System;
using System.CodeDom;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Json;
using System.Text;

namespace JsonTools
{
    /// <summary>
    /// Allows using Dictionary&lt;String,String&gt; and Dictionary&lt;String,Boolean&gt; types, and any others you'd like to add.
    /// Source: https://web.archive.org/web/20100317222656/my6solutions.com/post/2009/06/30/DataContractSerializer-DataContractJsonSerializer-JavaScriptSerializer-XmlSerializer-for-serialization.aspx
    /// </summary>
    public class JsonSurrogate : IDataContractSurrogate
    {
        /// <summary>
        /// Deserialize an object with added support for the types defined in this class.
        /// </summary>
        /// <typeparam name="T">Contract class</typeparam>
        /// <param name="json">JSON String</param>
        /// <param name="encoding">Text encoding</param>
        /// <returns>The deserialized object of type T</returns>
        public static T Deserialize<T>(String json, Encoding encoding)
        {
            if (encoding == null)
                encoding = new UTF8Encoding(false);
            DataContractJsonSerializer deserializer = new DataContractJsonSerializer(
                typeof(T), new Type[0], int.MaxValue, true, new JsonSurrogate(), false);
            using (MemoryStream stream = new MemoryStream(encoding.GetBytes(json)))
            {
                T result = (T)deserializer.ReadObject(stream);
                return result;
            }
        }

        // make sure all values in this are classes implementing JsonSurrogateObject.
        private static Dictionary<Type, Type> KnownTypes = 
            new Dictionary<Type, Type>()
            {
                {typeof(Dictionary<String, String>), typeof(SSDictionary)},
                {typeof(Dictionary<String, Boolean>), typeof(SBDictionary)}
            };

        #region Implemented surrogate dictionary classes

        [Serializable]
        public class SSDictionary : SurrogateDictionary<String>
        {
            public SSDictionary() : base() {}
            protected SSDictionary (SerializationInfo info, StreamingContext context) : base(info, context) {}
        }
        [Serializable]
        public class SBDictionary : SurrogateDictionary<Boolean>
        {
            public SBDictionary() : base() {}
            protected SBDictionary (SerializationInfo info, StreamingContext context) : base(info, context) {}
        }

        #endregion

        /// <summary>Small interface to easily extract the final value from the object.</summary>
        public interface JsonSurrogateObject
        {
            Object DeserializedObject { get; }
        }

        /// <summary>
        /// Class for deserializing any simple dictionary types with a string as key.
        /// </summary>
        /// <typeparam name="T">Any simple type that will be deserialized correctly.</typeparam>
            [Serializable]
        public abstract class SurrogateDictionary<T> : ISerializable, JsonSurrogateObject
        {
            public Object DeserializedObject { get { return dict; } }
            private Dictionary<String, T> dict;

            public SurrogateDictionary()
            {
                dict = new Dictionary<String, T>();
            }

            // deserialize
            protected SurrogateDictionary(SerializationInfo info, StreamingContext context)
            {
                dict = new Dictionary<String, T>();
                foreach (SerializationEntry entry in info)
                {
                    // This cast will only work for base types, of course.
                    dict.Add(entry.Name, (T)entry.Value);
                }
            }
            // serialize
            public void GetObjectData(SerializationInfo info, StreamingContext context)
            {
                foreach (String key in dict.Keys)
                {
                    info.AddValue(key, dict[key]);
                }
            }

        }

        /// <summary>
            /// Uses the KnownTypes dictionary to get the surrogate classes.
        /// </summary>
        /// <param name="type"></param>
        /// <returns></returns>
        public Type GetDataContractType(Type type)
        {
            Type returnType;
            if (KnownTypes.TryGetValue(type, out returnType))
            {
                return returnType;
            }
            return type;
        }

        public object GetObjectToSerialize(object obj, Type targetType)
        {
            throw new NotImplementedException();
        }

        /// <summary>
        ///     Gets the object out of the surrogate datacontract object. This function is the reason all surrogate objects need to implement the JsonSurrogateObject class.
        /// </summary>
        /// <param name="obj">Result of the deserialization</param>
        /// <param name="targetType">Expected target type of the deserialization</param>
        /// <returns></returns>
        public object GetDeserializedObject(object obj, Type targetType)
        {
            if (obj is JsonSurrogateObject)
            {
                return ((JsonSurrogateObject)obj).DeserializedObject;
            }
            return obj;
        }

        public Type GetReferencedTypeOnImport(string typeName, string typeNamespace, object customData)
        {
            return null;
        }

        #region not implemented

        public object GetCustomDataToExport(MemberInfo memberInfo, Type dataContractType)
        {
            throw new NotImplementedException();
        }

        public object GetCustomDataToExport(Type clrType, Type dataContractType)
        {
            throw new NotImplementedException();
        }

        public void GetKnownCustomDataTypes(Collection<Type> customDataTypes)
        {
            throw new NotImplementedException();
        }

        public CodeTypeDeclaration ProcessImportedType(CodeTypeDeclaration typeDeclaration, CodeCompileUnit compileUnit)
        {
            throw new NotImplementedException();
        }

        #endregion
    }
}

要向类中添加新的受支持类型,只需添加类,为其提供正确的构造函数和函数(请参阅SurrogateDictionary示例),确保其继承JsonSurrogateObject,并将其类型映射添加到KnownTypes字典。包含的SurrogateDictionary可以作为任何Dictionary<String,T>类型的基础,其中T是正确反序列化的任何类型。

调用它非常简单:

MyObjtype newObj = JsonSurrogate.Deserialize<MyObjtype>(jsonStr, encoding);

请注意,由于某些原因,这个东西在使用包含空格的键字符串时遇到了问题;他们根本不在最终名单中。可能只是因为它违反了json规范,我调用的api实现得很差,请注意;我不知道。无论如何,我通过正则表达式在原始json数据中用下划线替换它们,并在反序列化后修复字典来解决这个问题。

编辑:这是可行的,但使用Json.NET的公认答案要简单得多。留下这个,以防有人只需要BCL代码。

现成的.NET框架不支持它。一个明显的疏忽——并不是每个人都需要反序列化为具有命名财产的对象。所以,我最终推出了自己的:

VB.NET:

<Serializable()> Public Class StringStringDictionary
    Implements ISerializable
    Public dict As System.Collections.Generic.Dictionary(Of String, String)
    Public Sub New()
        dict = New System.Collections.Generic.Dictionary(Of String, String)
    End Sub
    Protected Sub New(info As SerializationInfo, _
          context As StreamingContext)
        dict = New System.Collections.Generic.Dictionary(Of String, String)
        For Each entry As SerializationEntry In info
            dict.Add(entry.Name, DirectCast(entry.Value, String))
        Next
    End Sub
    Public Sub GetObjectData(info As SerializationInfo, context As StreamingContext) Implements ISerializable.GetObjectData
        For Each key As String in dict.Keys
            info.AddValue(key, dict.Item(key))
        Next
    End Sub
End Class

与C#相同:

public class StringStringDictionary : ISerializable
{
    public System.Collections.Generic.Dictionary<string, string> dict;
    public StringStringDictionary()
    {
        dict = new System.Collections.Generic.Dictionary<string, string>();
    }
    protected StringStringDictionary(SerializationInfo info, StreamingContext context)
    {
        dict = new System.Collections.Generic.Dictionary<string, string>();
        foreach (SerializationEntry entry in info)
            dict.Add(entry.Name, (string)entry.Value);
    }
    public void GetObjectData(SerializationInfo info, StreamingContext context)
    {
        foreach (string key in dict.Keys)
            info.AddValue(key, dict[key]);
    }
}

调用方式:

string MyJsonString = "{ \"key1\": \"value1\", \"key2\": \"value2\"}";
System.Runtime.Serialization.Json.DataContractJsonSerializer dcjs = new
  System.Runtime.Serialization.Json.DataContractJsonSerializer(
    typeof(StringStringDictionary));
System.IO.MemoryStream ms = new
  System.IO.MemoryStream(Encoding.UTF8.GetBytes(MyJsonString));
StringStringDictionary myfields = (StringStringDictionary)dcjs.ReadObject(ms);
Response.Write("Value of key2: " + myfields.dict["key2"]);

很抱歉,C#和VB.NET混合使用…

Json.NET执行此操作。。。

string json = @"{""key1"":""value1"",""key2"":""value2""}";

var values = JsonConvert.DeserializeObject<Dictionary<string, string>>(json);

更多示例:使用Json.NET序列化集合