Getting MissingMethodException when using Manatee.trello to get list of users

Question

I have the following code which is intended to fetch a list of all the user of an organisation.

public static IEnumerable<Member> ListTrelloUsers()
    {
        var serializer = new ManateeSerializer();
        TrelloConfiguration.Serializer = serializer;
        TrelloConfiguration.Deserializer = serializer;
        TrelloConfiguration.JsonFactory = new ManateeFactory();
        TrelloConfiguration.RestClientProvider = new RestSharpClientProvider();
        TrelloAuthorization.Default.AppKey = ApplicationKey;
        TrelloAuthorization.Default.UserToken = GrandToken;

        var myOrganization = Member.Me.Organizations.FirstOrDefault().Id; //Exception thrown here.
        var orgToAddTo = new Organization(myOrganization);

        return orgToAddTo.Members.AsEnumerable();
    }

But I'm getting a

System.MissingMethodException

thrown on

RestSharp.IRestRequest RestSharp.RestRequest.AddFile(System.String, Byte[], System.String)

So why is this exception thrown and what should the correctly working code look like?

Clarifications

I will also accept working C#/ASP.Net MVC code that isn't based on Manatee.Trello as an answer. (Including pure API-calls.)

I have tried using the Organisation ID directly as

var orgToAddTo = new Organization(OrganisationId);

but that just caused the same exception to be thrown later when I make a call to the method's returned object (e.g. using Count()).

UPDATE: I tried setting the build to Release instead of Debug and now the (same) exception is instead thrown at

TrelloConfiguration.RestClientProvider = new RestSharpClientProvider();

Answer 1

This is an issue with RestSharp that I reported quite some time ago, though they deny that it's a problem. If you're using .Net 4.5+, you can try the Manatee.Trello.WebApi package instead of Manatee.Trello.RestSharp.

TrelloConfiguration.RestProvider = new WebApiClientProvider();

Here's my Trello card for tracking the issue. This and this are the RestSharp issues I created.

I have been able to recreate this as well, but have received no help from them to resolve it.

Answer 2

Apperently, the class with missing method is located in an assembly, which differ from the one, which you used while compiling the project. Double check and make sure both at compiling and at execution you use the same assembly with the aforementioned class. That is my best clue based on the info you've provided.

• basically, check project references and make sure, you use correct ones for the class-holding assembly.