1063
votes

Is there a way to deserialize JSON content into a C# 4 dynamic type? It would be nice to skip creating a bunch of classes in order to use the DataContractJsonSerializer.

28
If you want something 'dynamic', why not just use the get-style accessors that come with most JSON decoders that don't go to plain-old-object? (e.g. is there really a need for 'dynamic' object creation?) json.org has a bunch of links for C# JSON implementations.user166390
I'm working on a project that is trying to keep external dependencies to a minimum. So if it's possible to something with the stock .net serializers and types that would be preferred. Of course if it's not possible I'm hitting up json.org. Thanks!jswanson
I'm really surprised the C# team added 'dynamic' but then there is no way in the CLR to convert a JSON object to a dynamic CLR class instance.Frank Schwieterman
Unfortunately the accepted answer doesn't work in .NET 4 RTM. I posted an answer that helped me get going with this which might be useful to others.Drew Noakes
Update October 2018, this is how the magic happens: stackoverflow.com/a/48023576/4180382Ole EH Dufour

28 Answers

704
votes

If you are happy to have a dependency upon the System.Web.Helpers assembly, then you can use the Json class:

dynamic data = Json.Decode(json);

It is included with the MVC framework as an additional download to the .NET 4 framework. Be sure to give Vlad an upvote if that's helpful! However if you cannot assume the client environment includes this DLL, then read on.


An alternative deserialisation approach is suggested here. I modified the code slightly to fix a bug and suit my coding style. All you need is this code and a reference to System.Web.Extensions from your project:

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Dynamic;
using System.Linq;
using System.Text;
using System.Web.Script.Serialization;

public sealed class DynamicJsonConverter : JavaScriptConverter
{
    public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer)
    {
        if (dictionary == null)
            throw new ArgumentNullException("dictionary");

        return type == typeof(object) ? new DynamicJsonObject(dictionary) : null;
    }

    public override IDictionary<string, object> Serialize(object obj, JavaScriptSerializer serializer)
    {
        throw new NotImplementedException();
    }

    public override IEnumerable<Type> SupportedTypes
    {
        get { return new ReadOnlyCollection<Type>(new List<Type>(new[] { typeof(object) })); }
    }

    #region Nested type: DynamicJsonObject

    private sealed class DynamicJsonObject : DynamicObject
    {
        private readonly IDictionary<string, object> _dictionary;

        public DynamicJsonObject(IDictionary<string, object> dictionary)
        {
            if (dictionary == null)
                throw new ArgumentNullException("dictionary");
            _dictionary = dictionary;
        }

        public override string ToString()
        {
            var sb = new StringBuilder("{");
            ToString(sb);
            return sb.ToString();
        }

        private void ToString(StringBuilder sb)
        {
            var firstInDictionary = true;
            foreach (var pair in _dictionary)
            {
                if (!firstInDictionary)
                    sb.Append(",");
                firstInDictionary = false;
                var value = pair.Value;
                var name = pair.Key;
                if (value is string)
                {
                    sb.AppendFormat("{0}:\"{1}\"", name, value);
                }
                else if (value is IDictionary<string, object>)
                {
                    new DynamicJsonObject((IDictionary<string, object>)value).ToString(sb);
                }
                else if (value is ArrayList)
                {
                    sb.Append(name + ":[");
                    var firstInArray = true;
                    foreach (var arrayValue in (ArrayList)value)
                    {
                        if (!firstInArray)
                            sb.Append(",");
                        firstInArray = false;
                        if (arrayValue is IDictionary<string, object>)
                            new DynamicJsonObject((IDictionary<string, object>)arrayValue).ToString(sb);
                        else if (arrayValue is string)
                            sb.AppendFormat("\"{0}\"", arrayValue);
                        else
                            sb.AppendFormat("{0}", arrayValue);

                    }
                    sb.Append("]");
                }
                else
                {
                    sb.AppendFormat("{0}:{1}", name, value);
                }
            }
            sb.Append("}");
        }

        public override bool TryGetMember(GetMemberBinder binder, out object result)
        {
            if (!_dictionary.TryGetValue(binder.Name, out result))
            {
                // return null to avoid exception.  caller can check for null this way...
                result = null;
                return true;
            }

            result = WrapResultObject(result);
            return true;
        }

        public override bool TryGetIndex(GetIndexBinder binder, object[] indexes, out object result)
        {
            if (indexes.Length == 1 && indexes[0] != null)
            {
                if (!_dictionary.TryGetValue(indexes[0].ToString(), out result))
                {
                    // return null to avoid exception.  caller can check for null this way...
                    result = null;
                    return true;
                }

                result = WrapResultObject(result);
                return true;
            }

            return base.TryGetIndex(binder, indexes, out result);
        }

        private static object WrapResultObject(object result)
        {
            var dictionary = result as IDictionary<string, object>;
            if (dictionary != null)
                return new DynamicJsonObject(dictionary);

            var arrayList = result as ArrayList;
            if (arrayList != null && arrayList.Count > 0)
            {
                return arrayList[0] is IDictionary<string, object> 
                    ? new List<object>(arrayList.Cast<IDictionary<string, object>>().Select(x => new DynamicJsonObject(x))) 
                    : new List<object>(arrayList.Cast<object>());
            }

            return result;
        }
    }

    #endregion
}

You can use it like this:

string json = ...;

var serializer = new JavaScriptSerializer();
serializer.RegisterConverters(new[] { new DynamicJsonConverter() });

dynamic obj = serializer.Deserialize(json, typeof(object));

So, given a JSON string:

{
  "Items":[
    { "Name":"Apple", "Price":12.3 },
    { "Name":"Grape", "Price":3.21 }
  ],
  "Date":"21/11/2010"
}

The following code will work at runtime:

dynamic data = serializer.Deserialize(json, typeof(object));

data.Date; // "21/11/2010"
data.Items.Count; // 2
data.Items[0].Name; // "Apple"
data.Items[0].Price; // 12.3 (as a decimal)
data.Items[1].Name; // "Grape"
data.Items[1].Price; // 3.21 (as a decimal)
673
votes

It's pretty simple using Json.NET:

dynamic stuff = JsonConvert.DeserializeObject("{ 'Name': 'Jon Smith', 'Address': { 'City': 'New York', 'State': 'NY' }, 'Age': 42 }");

string name = stuff.Name;
string address = stuff.Address.City;

Also using Newtonsoft.Json.Linq:

dynamic stuff = JObject.Parse("{ 'Name': 'Jon Smith', 'Address': { 'City': 'New York', 'State': 'NY' }, 'Age': 42 }");

string name = stuff.Name;
string address = stuff.Address.City;

Documentation: Querying JSON with dynamic

305
votes

You can do this using System.Web.Helpers.Json - its Decode method returns a dynamic object which you can traverse as you like.

It's included in the System.Web.Helpers assembly (.NET 4.0).

var dynamicObject = Json.Decode(jsonString);
85
votes

.NET 4.0 has a built-in library to do this:

using System.Web.Script.Serialization;
JavaScriptSerializer jss = new JavaScriptSerializer();
var d = jss.Deserialize<dynamic>(str);

This is the simplest way.

83
votes

Simple "string JSON data" to object without any third-party DLL file:

WebClient client = new WebClient();
string getString = client.DownloadString("https://graph.facebook.com/zuck");

JavaScriptSerializer serializer = new JavaScriptSerializer();
dynamic item = serializer.Deserialize<object>(getString);
string name = item["name"];

//note: JavaScriptSerializer in this namespaces
//System.Web.Script.Serialization.JavaScriptSerializer

Note: You can also using your custom object.

Personel item = serializer.Deserialize<Personel>(getString);
29
votes

JsonFx can deserialize JSON content into dynamic objects.

Serialize to/from dynamic types (default for .NET 4.0):

var reader = new JsonReader(); var writer = new JsonWriter();

string input = @"{ ""foo"": true, ""array"": [ 42, false, ""Hello!"", null ] }";
dynamic output = reader.Read(input);
Console.WriteLine(output.array[0]); // 42
string json = writer.Write(output);
Console.WriteLine(json); // {"foo":true,"array":[42,false,"Hello!",null]}
27
votes

You can achieve that with the help of Newtonsoft.Json. Install it from NuGet and then:

using Newtonsoft.Json;

dynamic results = JsonConvert.DeserializeObject<dynamic>(YOUR_JSON);
23
votes

Another way using Newtonsoft.Json:

dynamic stuff = Newtonsoft.Json.JsonConvert.DeserializeObject("{ color: 'red', value: 5 }");
string color = stuff.color;
int value = stuff.value;
20
votes

I made a new version of the DynamicJsonConverter that uses Expando Objects. I used expando objects, because I wanted to Serialize the dynamic back into JSON using Json.NET.

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Dynamic;
using System.Web.Script.Serialization;

public static class DynamicJson
{
    public static dynamic Parse(string json)
    {
        JavaScriptSerializer jss = new JavaScriptSerializer();
        jss.RegisterConverters(new JavaScriptConverter[] { new DynamicJsonConverter() });

        dynamic glossaryEntry = jss.Deserialize(json, typeof(object)) as dynamic;
        return glossaryEntry;
    }

    class DynamicJsonConverter : JavaScriptConverter
    {
        public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer)
        {
            if (dictionary == null)
                throw new ArgumentNullException("dictionary");

            var result = ToExpando(dictionary);

            return type == typeof(object) ? result : null;
        }

        private static ExpandoObject ToExpando(IDictionary<string, object> dictionary)
        {
            var result = new ExpandoObject();
            var dic = result as IDictionary<String, object>;

            foreach (var item in dictionary)
            {
                var valueAsDic = item.Value as IDictionary<string, object>;
                if (valueAsDic != null)
                {
                    dic.Add(item.Key, ToExpando(valueAsDic));
                    continue;
                }
                var arrayList = item.Value as ArrayList;
                if (arrayList != null && arrayList.Count > 0)
                {
                    dic.Add(item.Key, ToExpando(arrayList));
                    continue;
                }

                dic.Add(item.Key, item.Value);
            }
            return result;
        }

        private static ArrayList ToExpando(ArrayList obj)
        {
            ArrayList result = new ArrayList();

            foreach (var item in obj)
            {
                var valueAsDic = item as IDictionary<string, object>;
                if (valueAsDic != null)
                {
                    result.Add(ToExpando(valueAsDic));
                    continue;
                }

                var arrayList = item as ArrayList;
                if (arrayList != null && arrayList.Count > 0)
                {
                    result.Add(ToExpando(arrayList));
                    continue;
                }

                result.Add(item);
            }
            return result;
        }

        public override IDictionary<string, object> Serialize(object obj, JavaScriptSerializer serializer)
        {
            throw new NotImplementedException();
        }

        public override IEnumerable<Type> SupportedTypes
        {
            get { return new ReadOnlyCollection<Type>(new List<Type>(new[] { typeof(object) })); }
        }
    }
}
10
votes

Creating dynamic objects with Newtonsoft.Json works really great.

//json is your string containing the JSON value
dynamic data = JsonConvert.DeserializeObject<dynamic>(json);

Now you can access the data object just like if it was a regular object. This is the JSON object we currently have as an example:

{ "ID":123,"Name":"Jack","Numbers":[1, 2, 3] }

This is how you access it after deserialization:

data.ID //Retrieve the int
data.Name //Retrieve the string
data.Numbers[0] //Retrieve the first element in the array
9
votes

I use http://json2csharp.com/ to get a class representing the JSON object.

Input:

{
   "name":"John",
   "age":31,
   "city":"New York",
   "Childs":[
      {
         "name":"Jim",
         "age":11
      },
      {
         "name":"Tim",
         "age":9
      }
   ]
}

Output:

public class Child
{
    public string name { get; set; }
    public int age { get; set; }
}

public class Person
{
    public string name { get; set; }
    public int age { get; set; }
    public string city { get; set; }
    public List<Child> Childs { get; set; }
}

After that I use Newtonsoft.Json to fill the class:

using Newtonsoft.Json;

namespace GitRepositoryCreator.Common
{
    class JObjects
    {
        public static string Get(object p_object)
        {
            return JsonConvert.SerializeObject(p_object);
        }
        internal static T Get<T>(string p_object)
        {
            return JsonConvert.DeserializeObject<T>(p_object);
        }
    }
}

You can call it like this:

Person jsonClass = JObjects.Get<Person>(stringJson);

string stringJson = JObjects.Get(jsonClass);

PS:

If your JSON variable name is not a valid C# name (name starts with $) you can fix that like this:

public class Exception
{
   [JsonProperty(PropertyName = "$id")]
   public string id { get; set; }
   public object innerException { get; set; }
   public string message { get; set; }
   public string typeName { get; set; }
   public string typeKey { get; set; }
   public int errorCode { get; set; }
   public int eventId { get; set; }
}
8
votes

The simplest way is:

Just include this DLL file.

Use the code like this:

dynamic json = new JDynamic("{a:'abc'}");
// json.a is a string "abc"

dynamic json = new JDynamic("{a:3.1416}");
// json.a is 3.1416m

dynamic json = new JDynamic("{a:1}");
// json.a is

dynamic json = new JDynamic("[1,2,3]");
/json.Length/json.Count is 3
// And you can use json[0]/ json[2] to get the elements

dynamic json = new JDynamic("{a:[1,2,3]}");
//json.a.Length /json.a.Count is 3.
// And you can use  json.a[0]/ json.a[2] to get the elements

dynamic json = new JDynamic("[{b:1},{c:1}]");
// json.Length/json.Count is 2.
// And you can use the  json[0].b/json[1].c to get the num.
6
votes

You can extend the JavaScriptSerializer to recursively copy the dictionary it created to expando object(s) and then use them dynamically:

static class JavaScriptSerializerExtensions
{
    public static dynamic DeserializeDynamic(this JavaScriptSerializer serializer, string value)
    {
        var dictionary = serializer.Deserialize<IDictionary<string, object>>(value);
        return GetExpando(dictionary);
    }

    private static ExpandoObject GetExpando(IDictionary<string, object> dictionary)
    {
        var expando = (IDictionary<string, object>)new ExpandoObject();

        foreach (var item in dictionary)
        {
            var innerDictionary = item.Value as IDictionary<string, object>;
            if (innerDictionary != null)
            {
                expando.Add(item.Key, GetExpando(innerDictionary));
            }
            else
            {
                expando.Add(item.Key, item.Value);
            }
        }

        return (ExpandoObject)expando;
    }
}

Then you just need to having a using statement for the namespace you defined the extension in (consider just defining them in System.Web.Script.Serialization... another trick is to not use a namespace, then you don't need the using statement at all) and you can consume them like so:

var serializer = new JavaScriptSerializer();
var value = serializer.DeserializeDynamic("{ 'Name': 'Jon Smith', 'Address': { 'City': 'New York', 'State': 'NY' }, 'Age': 42 }");

var name = (string)value.Name; // Jon Smith
var age = (int)value.Age;      // 42

var address = value.Address;
var city = (string)address.City;   // New York
var state = (string)address.State; // NY
6
votes

You can use using Newtonsoft.Json

var jRoot = 
 JsonConvert.DeserializeObject<dynamic>(Encoding.UTF8.GetString(resolvedEvent.Event.Data));

resolvedEvent.Event.Data is my response getting from calling core Event .

6
votes

Another option is to "Paste JSON as classes" so it can be deserialised quick and easy.

  1. Simply copy your entire JSON
  2. In Visual Studio: Click EditPaste SpecialPaste JSON as classes

Here is a better explanation n piccas... ‘Paste JSON As Classes’ in ASP.NET and Web Tools 2012.2 RC

5
votes

I am using like this in my code and it's working fine

using System.Web.Script.Serialization;
JavaScriptSerializer oJS = new JavaScriptSerializer();
RootObject oRootObject = new RootObject();
oRootObject = oJS.Deserialize<RootObject>(Your JSon String);
5
votes

Look at the article I wrote on CodeProject, one that answers the question precisely:

Dynamic types with JSON.NET

There is way too much for re-posting it all here, and even less point since that article has an attachment with the key/required source file.

5
votes

Try this:

  var units = new { Name = "Phone", Color= "White" };
    var jsonResponse = JsonConvert.DeserializeAnonymousType(json, units);
4
votes

For that I would use JSON.NET to do the low-level parsing of the JSON stream and then build up the object hierarchy out of instances of the ExpandoObject class.

4
votes

To get an ExpandoObject:

using Newtonsoft.Json;
using Newtonsoft.Json.Converters;

Container container = JsonConvert.Deserialize<Container>(jsonAsString, new ExpandoObjectConverter());
4
votes

Deserializing in JSON.NET can be dynamic using the JObject class, which is included in that library. My JSON string represents these classes:

public class Foo {
   public int Age {get;set;}
   public Bar Bar {get;set;}
}

public class Bar {
   public DateTime BDay {get;set;}
}

Now we deserialize the string WITHOUT referencing the above classes:

var dyn = JsonConvert.DeserializeObject<JObject>(jsonAsFooString);

JProperty propAge = dyn.Properties().FirstOrDefault(i=>i.Name == "Age");
if(propAge != null) {
    int age = int.Parse(propAge.Value.ToString());
    Console.WriteLine("age=" + age);
}

//or as a one-liner:
int myage = int.Parse(dyn.Properties().First(i=>i.Name == "Age").Value.ToString());

Or if you want to go deeper:

var propBar = dyn.Properties().FirstOrDefault(i=>i.Name == "Bar");
if(propBar != null) {
    JObject o = (JObject)propBar.First();
    var propBDay = o.Properties().FirstOrDefault (i => i.Name=="BDay");
    if(propBDay != null) {
        DateTime bday = DateTime.Parse(propBDay.Value.ToString());
        Console.WriteLine("birthday=" + bday.ToString("MM/dd/yyyy"));
    }
}

//or as a one-liner:
DateTime mybday = DateTime.Parse(((JObject)dyn.Properties().First(i=>i.Name == "Bar").First()).Properties().First(i=>i.Name == "BDay").Value.ToString());

See post for a complete example.

4
votes

The object you want DynamicJSONObject is included in the System.Web.Helpers.dll from the ASP.NET Web Pages package, which is part of WebMatrix.

4
votes

There is a lightweight JSON library for C# called SimpleJson.

It supports .NET 3.5+, Silverlight and Windows Phone 7.

It supports dynamic for .NET 4.0

It can also be installed as a NuGet package

Install-Package SimpleJson
4
votes

Use DataSet(C#) with JavaScript. A simple function for creating a JSON stream with DataSet input. Create JSON content like (multi table dataset):

[[{a:1,b:2,c:3},{a:3,b:5,c:6}],[{a:23,b:45,c:35},{a:58,b:59,c:45}]]

Just client side, use eval. For example,

var d = eval('[[{a:1,b:2,c:3},{a:3,b:5,c:6}],[{a:23,b:45,c:35},{a:58,b:59,c:45}]]')

Then use:

d[0][0].a // out 1 from table 0 row 0

d[1][1].b // out 59 from table 1 row 1

// Created by Behnam Mohammadi And Saeed Ahmadian
public string jsonMini(DataSet ds)
{
    int t = 0, r = 0, c = 0;
    string stream = "[";

    for (t = 0; t < ds.Tables.Count; t++)
    {
        stream += "[";
        for (r = 0; r < ds.Tables[t].Rows.Count; r++)
        {
            stream += "{";
            for (c = 0; c < ds.Tables[t].Columns.Count; c++)
            {
                stream += ds.Tables[t].Columns[c].ToString() + ":'" +
                          ds.Tables[t].Rows[r][c].ToString() + "',";
            }
            if (c>0)
                stream = stream.Substring(0, stream.Length - 1);
            stream += "},";
        }
        if (r>0)
            stream = stream.Substring(0, stream.Length - 1);
        stream += "],";
    }
    if (t>0)
        stream = stream.Substring(0, stream.Length - 1);
    stream += "];";
    return stream;
}
3
votes

How to parse easy JSON content with dynamic & JavaScriptSerializer

Please add reference of System.Web.Extensions and add this namespace using System.Web.Script.Serialization; at top:

public static void EasyJson()
{
    var jsonText = @"{
        ""some_number"": 108.541,
        ""date_time"": ""2011-04-13T15:34:09Z"",
        ""serial_number"": ""SN1234""
    }";

    var jss = new JavaScriptSerializer();
    var dict = jss.Deserialize<dynamic>(jsonText);

    Console.WriteLine(dict["some_number"]);
    Console.ReadLine();
}

How to parse nested & complex json with dynamic & JavaScriptSerializer

Please add reference of System.Web.Extensions and add this namespace using System.Web.Script.Serialization; at top:

public static void ComplexJson()
{
    var jsonText = @"{
        ""some_number"": 108.541,
        ""date_time"": ""2011-04-13T15:34:09Z"",
        ""serial_number"": ""SN1234"",
        ""more_data"": {
            ""field1"": 1.0,
            ""field2"": ""hello""
        }
    }";

    var jss = new JavaScriptSerializer();
    var dict = jss.Deserialize<dynamic>(jsonText);

    Console.WriteLine(dict["some_number"]);
    Console.WriteLine(dict["more_data"]["field2"]);
    Console.ReadLine();
}
3
votes

With Cinchoo ETL - an open source library available to parse JSON into a dynamic object:

string json = @"{
    ""key1"": [
        {
            ""action"": ""open"",
            ""timestamp"": ""2018-09-05 20:46:00"",
            ""url"": null,
            ""ip"": ""66.102.6.98""
        }
    ]
}";
using (var p = ChoJSONReader.LoadText(json)
    .WithJSONPath("$.*")
    )
{
    foreach (var rec in p)
    {
        Console.WriteLine("Action: " + rec.action);
        Console.WriteLine("Timestamp: " + rec.timestamp);
        Console.WriteLine("URL: " + rec.url);
        Console.WriteLine("IP address: " + rec.ip);
    }
}

Output:

Action: open
Timestamp: 2018-09-05 20:46:00
URL: http://www.google.com
IP address: 66.102.6.98

Disclaimer: I'm the author of this library.

2
votes

I want to do this programmatically in unit tests, I do have the luxury of typing it out.

My solution is:

var dict = JsonConvert.DeserializeObject<ExpandoObject>(json) as IDictionary<string, object>;

Now I can assert that

dict.ContainsKey("ExpectedProperty");
1
votes

try this way!

JSON example:

[{
    "id": 140,
    "group": 1,
    "text": "xxx",
    "creation_date": 123456,
    "created_by": "[email protected]",
    "tags": ["xxxxx"]
  }, {
    "id": 141,
    "group": 1,
    "text": "xxxx",
    "creation_date": 123456,
    "created_by": "[email protected]",
    "tags": ["xxxxx"]
}]

C# code:

var jsonString = (File.ReadAllText(Path.Combine(Directory.GetCurrentDirectory(),"delete_result.json")));
var objects = JsonConvert.DeserializeObject<dynamic>(jsonString);
foreach(var o in objects)
{
    Console.WriteLine($"{o.id.ToString()}");
}