Binding in Ninject - generic arguments provided doesn't equal the arity of the generic type definition?

Question

Trying to use ninject to bind my interface to a concrete class but I must be missing something and can't get it work.

System.ArgumentException was unhandled by user code
  HResult=-2147024809
  Message=The number of generic arguments provided doesn't equal the arity of the generic type definition.
Parameter name: instantiation
  Source=mscorlib
  ParamName=instantiation
  StackTrace:
       at System.RuntimeType.MakeGenericType(Type[] instantiation)
       at Ninject.Activation.Providers.StandardProvider.GetImplementationType(Type service) in StandardProvider.cs:line 126
       at Ninject.Activation.Providers.StandardProvider.Create(IContext context) in StandardProvider.cs:line 77
       at Ninject.Activation.Context.Resolve() inContext.cs:line 157
       at Ninject.KernelBase.<>c__DisplayClass10.<Resolve>b__c(IBinding binding) in KernelBase.cs:line 386
       at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
       at System.Linq.Enumerable.SingleOrDefault[TSource](IEnumerable`1 source)
       at Ninject.Planning.Targets.Target`1.GetValue(Type service, IContext parent) in Target.cs:line 197
       at Ninject.Planning.Targets.Target`1.ResolveWithin(IContext parent) inTarget.cs:line 165
       at Ninject.Activation.Providers.StandardProvider.GetValue(IContext context, ITarget target) in StandardProvider.cs:line 114
       at Ninject.Activation.Providers.StandardProvider.<>c__DisplayClass4.<Create>b__2(ITarget target) in StandardProvider.cs:line 96
       at System.Linq.Enumerable.WhereSelectArrayIterator`2.MoveNext()
       at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
       at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
       at Ninject.Activation.Providers.StandardProvider.Create(IContext context) in StandardProvider.cs:line 96
       at Ninject.Activation.Context.Resolve() inContext.cs:line 157
       at Ninject.KernelBase.<>c__DisplayClass10.<Resolve>b__c(IBinding binding) in KernelBase.cs:line 386
       at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
       at System.Linq.Enumerable.SingleOrDefault[TSource](IEnumerable`1 source)
       at Ninject.Planning.Targets.Target`1.GetValue(Type service, IContext parent) inTarget.cs:line 197
       at Ninject.Planning.Targets.Target`1.ResolveWithin(IContext parent) inTarget.cs:line 165
       at Ninject.Activation.Providers.StandardProvider.GetValue(IContext context, ITarget target) in StandardProvider.cs:line 114
       at Ninject.Activation.Providers.StandardProvider.<>c__DisplayClass4.<Create>b__2(ITarget target) in StandardProvider.cs:line 96
       at System.Linq.Enumerable.WhereSelectArrayIterator`2.MoveNext()
       at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
       at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
       at Ninject.Activation.Providers.StandardProvider.Create(IContext context) in StandardProvider.cs:line 96
       at Ninject.Activation.Context.Resolve() inContext.cs:line 157
       at Ninject.KernelBase.<>c__DisplayClass10.<Resolve>b__c(IBinding binding) in KernelBase.cs:line 386
       at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
       at System.Linq.Enumerable.SingleOrDefault[TSource](IEnumerable`1 source)
       at PriceCheck.Api.Models.Ninject.NinjectScope.GetService(Type serviceType) in NinjectScope.cs:line 24
       at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.GetInstanceOrActivator(HttpRequestMessage request, Type controllerType, Func`1& activator)
       at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType)
  InnerException:

Crashes here

   public object GetService(Type serviceType)
        {
            IRequest request = resolutionRoot.CreateRequest(serviceType, null, new Parameter[0], true, true);
            return resolutionRoot.Resolve(request).SingleOrDefault();
        }



  public interface IResponseResult
    {
       void AddError(string key, string errorMessage);
       bool IsValid();
       Dictionary<string, string> Errors { get; }

       ResponseBase Status { get; set; }
    }


 public class ResponseResult<T> : IResponseResult
    {
        public ResponseResult()
        {
            Errors = new Dictionary<string, string>();
            Status = new ResponseBase();
        }

        public void AddError(string key, string errorMessage)
        {
            if (!Errors.ContainsKey(key))
            {
                Errors.Add(key, errorMessage);
            }        
        }

        public bool IsValid()
        {
            if (Errors.Count > 0)
            {
                return false;
            }

            return true;
        }

        public Dictionary<string, string> Errors { get; private set; }
        public T Response { get; set; }

        public ResponseBase  Status { get; set; }
    }


Bind(typeof(IResponseResult)).To(typeof(ResponseResult<>));

IResponseResult has no generic type argument. But ResponseResult does have, and you don't specify to which one you want to bind it. — treze, Apr 21 '13 at 14:25

score 2 · Accepted Answer · edited May 23 '17 at 12:14

You're not really providing a 'constructed generic type' for the service.
Generics -Open and closed constructed Types
What exactly is an "open generic type" in .NET?

Ninject inside actually tries to make one - but expects generic arguments which you don't have.

Type.MakeGenericType(service.GetGenericArguments())

I'm not sure what did you have in mind - and how to resolve something like that.

You could try ToProvider or setting a provider - but you're still missing something.

Binding in Ninject - generic arguments provided doesn't equal the arity of the generic type definition?

1 Answers1