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

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

其他回答

我的方法直接反序列化为IDictionary,中间没有JObject或ExpandObject。代码使用转换器,该转换器基本上是从JSON.NET源代码中的ExpandoObjectConverter类复制的,但使用IDictionary而不是ExpandoObject。

用法:

var settings = new JsonSerializerSettings()
{
    Converters = { new DictionaryConverter() },
};
var result = JsonConvert.DeserializeObject<IDictionary<string, object>>(json, settings);

代码:

// based on ExpandoObjectConverter, but using arrays instead of IList, to behave similar to System.Web.Script.Serialization.JavaScriptSerializer
public class DictionaryConverter : JsonConverter
{
    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        return ReadValue(reader);
    }

    public override bool CanConvert(Type objectType)
    {
        return (objectType == typeof(IDictionary<string, object>));
    }

    public override bool CanWrite
    {
        get { return false; }
    }

    private object ReadValue(JsonReader reader)
    {
        while (reader.TokenType == JsonToken.Comment)
        {
            if (!reader.Read())
                throw JsonSerializationExceptionCreate(reader, "Unexpected end when reading IDictionary<string, object>.");
        }

        switch (reader.TokenType)
        {
            case JsonToken.StartObject:
                return ReadObject(reader);
            case JsonToken.StartArray:
                return ReadList(reader);
            default:
                if (IsPrimitiveToken(reader.TokenType))
                    return reader.Value;

                throw JsonSerializationExceptionCreate(reader, string.Format(CultureInfo.InvariantCulture, "Unexpected token when converting IDictionary<string, object>: {0}", reader.TokenType));
        }
    }

    private object ReadList(JsonReader reader)
    {
        List<object> list = new List<object>();

        while (reader.Read())
        {
            switch (reader.TokenType)
            {
                case JsonToken.Comment:
                    break;
                default:
                    object v = ReadValue(reader);

                    list.Add(v);
                    break;
                case JsonToken.EndArray:
                    return list;
            }
        }

        throw JsonSerializationExceptionCreate(reader, "Unexpected end when reading IDictionary<string, object>.");
    }

    private object ReadObject(JsonReader reader)
    {
        IDictionary<string, object> dictionary = new Dictionary<string, object>();
        while (reader.Read())
        {
            switch (reader.TokenType)
            {
                case JsonToken.PropertyName:
                    string propertyName = reader.Value.ToString();

                    if (!reader.Read())
                        throw JsonSerializationExceptionCreate(reader, "Unexpected end when reading IDictionary<string, object>.");

                    object v = ReadValue(reader);

                    dictionary[propertyName] = v;
                    break;
                case JsonToken.Comment:
                    break;
                case JsonToken.EndObject:
                    return dictionary;
            }
        }

        throw JsonSerializationExceptionCreate(reader, "Unexpected end when reading IDictionary<string, object>.");
    }

    //based on internal Newtonsoft.Json.JsonReader.IsPrimitiveToken
    internal static bool IsPrimitiveToken(JsonToken token)
    {
        switch (token)
        {
            case JsonToken.Integer:
            case JsonToken.Float:
            case JsonToken.String:
            case JsonToken.Boolean:
            case JsonToken.Undefined:
            case JsonToken.Null:
            case JsonToken.Date:
            case JsonToken.Bytes:
                return true;
            default:
                return false;
        }
    }

    // based on internal Newtonsoft.Json.JsonSerializationException.Create
    private static JsonSerializationException JsonSerializationExceptionCreate(JsonReader reader, string message, Exception ex = null)
    {
        return JsonSerializationExceptionCreate(reader as IJsonLineInfo, reader.Path, message, ex);
    }

    // based on internal Newtonsoft.Json.JsonSerializationException.Create
    private static JsonSerializationException JsonSerializationExceptionCreate(IJsonLineInfo lineInfo, string path, string message, Exception ex)
    {
        message = JsonPositionFormatMessage(lineInfo, path, message);

        return new JsonSerializationException(message, ex);
    }

    // based on internal Newtonsoft.Json.JsonPosition.FormatMessage
    internal static string JsonPositionFormatMessage(IJsonLineInfo lineInfo, string path, string message)
    {
        if (!message.EndsWith(Environment.NewLine))
        {
            message = message.Trim();

            if (!message.EndsWith(".", StringComparison.Ordinal))
                message += ".";

            message += " ";
        }

        message += string.Format(CultureInfo.InvariantCulture, "Path '{0}'", path);

        if (lineInfo != null && lineInfo.HasLineInfo())
            message += string.Format(CultureInfo.InvariantCulture, ", line {0}, position {1}", lineInfo.LineNumber, lineInfo.LinePosition);

        message += ".";

        return message;
    }
}

我只需要解析一个嵌套的字典

{
    "x": {
        "a": 1,
        "b": 2,
        "c": 3
    }
}

其中JsonConvert.DeserializeObject没有帮助。我发现了以下方法:

var dict = JObject.Parse(json).SelectToken("x").ToObject<Dictionary<string, int>>();

SelectToken允许您深入到所需的字段。您甚至可以指定一个类似“x.y.z”的路径,以进一步深入JSON对象。

System.Text.Json

这现在可以使用.NET Core 3.0内置的System.Text.Json来完成。现在可以在不使用第三方库的情况下反序列化JSON。

var json = @"{""key1"":""value1"",""key2"":""value2""}";
var values = JsonSerializer.Deserialize<Dictionary<string, string>>(json);

如果使用.NET标准或.NET Framework,也可以在NuGet包System.Text.Json中获得。


确保阅读并理解:

https://github.com/dotnet/runtime/issues/30452

对于那些在互联网上搜索并偶然发现这篇文章的人,我写了一篇关于如何使用JavaScriptSerializer类的博客文章。

阅读更多。。。http://procbits.com/2011/04/21/quick-json-serializationdeserialization-in-c/

下面是一个示例:

var json = "{\"id\":\"13\", \"value\": true}";
var jss = new JavaScriptSerializer();
var table = jss.Deserialize<dynamic>(json);
Console.WriteLine(table["id"]);
Console.WriteLine(table["value"]);

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…