Deserialize json object into dynamic object using Json.net

Json.NET allows us to do this:

dynamic d = JObject.Parse("{number:1000, str:'string', array: [1,2,3,4,5,6]}");

Console.WriteLine(d.number);
Console.WriteLine(d.str);
Console.WriteLine(d.array.Count);

Output:

 1000
 string
 6

Documentation here: LINQ to JSON with Json.NET

See also JObject.Parse and JArray.Parse

As of Json.NET 4.0 Release 1, there is native dynamic support:

[Test]
public void DynamicDeserialization()
{
    dynamic jsonResponse = JsonConvert.DeserializeObject("{\"message\":\"Hi\"}");
    jsonResponse.Works = true;
    Console.WriteLine(jsonResponse.message); // Hi
    Console.WriteLine(jsonResponse.Works); // True
    Console.WriteLine(JsonConvert.SerializeObject(jsonResponse)); // {"message":"Hi","Works":true}
    Assert.That(jsonResponse, Is.InstanceOf<dynamic>());
    Assert.That(jsonResponse, Is.TypeOf<JObject>());
}

And, of course, the best way to get the current version is via NuGet.

Updated (11/12/2014) to address comments:

This works perfectly fine. If you inspect the type in the debugger you will see that the value is, in fact, dynamic. The underlying type is a JObject. If you want to control the type (like specifying ExpandoObject, then do so.