Converting JObject to a dynamic object

Question

I am calling a REST endpoint from C# and I am receiving json which gets serialized into an object. One of the properties on this object is a dynamic property. The value of the dynamic property is set as a anonymous object on the server site like this:

myObject.MyDynamicProp = new { Id = "MyId2134", Name = "MyName" };

On the client site the value of the dynamic property from the json serialization is a JObject containing the following value:

{{
  "id": "MyId2134",
  "Name": "MyName"
}}

I would have expected to be able to access the properties like this:

var s = myObject.MyDynamicProp.Name;

but it does not find the Name property instead I have to get the value like this:

var s = myObject.MyDynamicProp["Name"].Value;

I tried converting the JObject into a dynamic object like this but it returns JObject:

var dyn = myObject.MyDynamicProp.ToObject<dynamic>();

How can I convert the dynamic property value such that I can call its properties directly?

var s = myObject.MyDynamicProp.Name;

UPDATE ...

I ran the following

 dynamic d = JsonConvert.DeserializeObject("{\"MyDynamicProp\": {\"id\": \"MyId2134\", \"Name\": \"MyName\"}}");
 string name = d.MyDynamicProp.Name;

Which gives me the following the error:

 {Microsoft.CSharp.RuntimeBinder.RuntimeBinderException:    `Newtonsoft.Json.Linq.JObject' does not contain a definition for `MyDynamicProp'
  at Microsoft.Scripting.Interpreter.ThrowInstruction.Run (Microsoft.Scripting.Interpreter.InterpretedFrame frame) [0x00027]

I would like to add that this is an Xamarin iOS project and the code is located in a PCL library.

---

I assumed there was a problem with my code but it looks like it is not possible to use dynamic types within a Xamarin iOS project. https://developer.xamarin.com/guides/ios/advanced_topics/limitations/

Solution

It is actually quite easy. Instead of using var use dynamic on your JObject and you will be fine:

dynamic do = myObject.MyDynamicProp;

string name = do.Name;

From your fragment:

dynamic d = JsonConvert.DeserializeObject("{\"MyDynamicProp\": {\"id\": \"MyId2134\", \"Name\": \"MyName\"}}");
string name = d.MyDynamicProp.Name;

Console.WriteLine(name); // writes MyName

Why this works: As Richard explained, JObject derives indirectly from JToken which implements IDynamicMetaObjectProvider. It is that interface that allows dynamic to work.

Comments

[Richard]

Why this works: JObject derives indirectly from JToken which implements IDynamicMetaObjectProvider. It is that interface that allows dynamic to work.

[Patrick Hofman]

Yes, indeed. Thanks Richard. Can I append that to my answer?

[doorman]

Thanks for your quick reply but even if I use dynamic instead of var I get "Unknown member: Name" when I call the property.

[Patrick Hofman]

It is Name, not name.

[doorman]

The precise exception I get is {Microsoft.CSharp.RuntimeBinder.RuntimeBinderException: Newtonsoft.Json.Linq.JObject' does not contain a definition for Name' ...

[doorman]

Thanks for your suggestions. Please see my updated code. I also added that this is an Xamarin iOS project and the code is running within a PCL library.

[Patrick Hofman]

Okay, that could be a reason indeed. I have no experience on that. It does seem to come a long way, so I think it should be possible.

[Patrick Hofman]

Can you give it a try with a regular dynamic variable?