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

我确实发现.NET有一种内置方式,可以通过3.5 System.Web.Extensions程序集中的System.Web.Script.Serialization.JavaScriptSerializer类型将JSON字符串转换为Dictionary<string,Object>。使用方法DeserializeObject(String)。

我在对静态.net页面方法进行内容类型为“application/json”的ajax发布(通过jquery)时偶然发现了这一点,并看到该方法(只有一个Object类型的参数)神奇地收到了这个字典。

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;
    }
}

如果您追求的是一种轻量级的、无添加引用的方法,那么我刚才写的这段代码可能会奏效(尽管我不能100%保证健壮性)。

using System;
using System.Collections.Generic;
using System.Text;
using System.Text.RegularExpressions;

public Dictionary<string, object> ParseJSON(string json)
{
    int end;
    return ParseJSON(json, 0, out end);
}
private Dictionary<string, object> ParseJSON(string json, int start, out int end)
{
    Dictionary<string, object> dict = new Dictionary<string, object>();
    bool escbegin = false;
    bool escend = false;
    bool inquotes = false;
    string key = null;
    int cend;
    StringBuilder sb = new StringBuilder();
    Dictionary<string, object> child = null;
    List<object> arraylist = null;
    Regex regex = new Regex(@"\\u([0-9a-z]{4})", RegexOptions.IgnoreCase);
    int autoKey = 0;
    for (int i = start; i < json.Length; i++)
    {
        char c = json[i];
        if (c == '\\') escbegin = !escbegin;
        if (!escbegin)
        {
            if (c == '"')
            {
                inquotes = !inquotes;
                if (!inquotes && arraylist != null)
                {
                    arraylist.Add(DecodeString(regex, sb.ToString()));
                    sb.Length = 0;
                }
                continue;
            }
            if (!inquotes)
            {
                switch (c)
                {
                    case '{':
                        if (i != start)
                        {
                            child = ParseJSON(json, i, out cend);
                            if (arraylist != null) arraylist.Add(child);
                            else
                            {
                                dict.Add(key, child);
                                key = null;
                            }
                            i = cend;
                        }
                        continue;
                    case '}':
                        end = i;
                        if (key != null)
                        {
                            if (arraylist != null) dict.Add(key, arraylist);
                            else dict.Add(key, DecodeString(regex, sb.ToString()));
                        }
                        return dict;
                    case '[':
                        arraylist = new List<object>();
                        continue;
                    case ']':
                        if (key == null)
                        {
                            key = "array" + autoKey.ToString();
                            autoKey++;
                        }
                        if (arraylist != null && sb.Length > 0)
                        {
                            arraylist.Add(sb.ToString());
                            sb.Length = 0;
                        }
                        dict.Add(key, arraylist);
                        arraylist = null;
                        key = null;
                        continue;
                    case ',':
                        if (arraylist == null && key != null)
                        {
                            dict.Add(key, DecodeString(regex, sb.ToString()));
                            key = null;
                            sb.Length = 0;
                        }
                        if (arraylist != null && sb.Length > 0)
                        {
                            arraylist.Add(sb.ToString());
                            sb.Length = 0;
                        }
                       continue;
                    case ':':
                        key = DecodeString(regex, sb.ToString());
                        sb.Length = 0;
                        continue;
                }
            }
        }
        sb.Append(c);
        if (escend) escbegin = false;
        if (escbegin) escend = true;
        else escend = false;
    }
    end = json.Length - 1;
    return dict; //theoretically shouldn't ever get here
}
private string DecodeString(Regex regex, string str)
{
    return Regex.Unescape(regex.Replace(str, match => char.ConvertFromUtf32(Int32.Parse(match.Groups[1].Value, System.Globalization.NumberStyles.HexNumber))));
}

[我意识到这违反了OP限制#1,但从技术上讲,你没有写,我写了]

根据上面的评论,尝试JsonConvert.DeserializeObject<Dictionary<string,dynamic>(json)

var json = @"{""key1"":1,""key2"":""value2"", ""object1"":{""property1"":""value1"",""property2"":[2,3,4,5,6,7]}}";
var parsedObject = JsonConvert.DeserializeObject<Dictionary<string,dynamic>>(json);

似乎甚至适用于复杂的对象和列表。

您可以使用Tiny JSON

string json = "{\"key1\":\"value1\", \"key2\":\"value2\"}";
IDictionary<string, string> dict = Tiny.Json.Decode<Dictionary<string, string>>(json);

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