I'm very new to using Unity, but my problem is that whenever I call my web service, I get an exception stating that
"Make sure that the controller has a parameterless public constructor"
I've followed multiple tutorials and I still get the same issue.
In the Register function of my WebApiConfig class, I have
var container = new UnityContainer();
container.RegisterType<IValidator, Validator>(new HierarchicalLifetimeManager());
config.DependencyResolver = new UnityResolver(container);
Here is my UnityResolver class
using Microsoft.Practices.Unity;
using System;
using System.Collections.Generic;
using System.Web.Http.Dependencies;
public class UnityResolver : IDependencyResolver
{
protected IUnityContainer container;
public UnityResolver(IUnityContainer container)
{
if (container == null)
{
throw new ArgumentNullException("container");
}
this.container = container;
}
public object GetService(Type serviceType)
{
try
{
return container.Resolve(serviceType);
}
catch (ResolutionFailedException)
{
return null;
}
}
public IEnumerable<object> GetServices(Type serviceType)
{
try
{
return container.ResolveAll(serviceType);
}
catch (ResolutionFailedException)
{
return new List<object>();
}
}
public IDependencyScope BeginScope()
{
var child = container.CreateChildContainer();
return new UnityResolver(child);
}
public void Dispose()
{
container.Dispose();
}
}
I have not registered any controllers, as every tutorial claims that I don't need to do this. Here is my actual controller
public class Controller: ApiController
{
private IValidator _validator;
public Controller(IValidator validator)
{
this._validator = validator;
}
[HttpPost]
public void ReceiveIPN()
{
}
}
Does anyone have any ideas as to what I can be doing wrong? Thanks!
EDIT 1: Here is the "implementation" of the Validator class. It's pretty empty, because I didn't want to introduce a bug here until I resolved the Unity issue.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
public class Validator: IValidator
{
public bool ValidateIPN(string body)
{
throw new NotImplementedException();
}
}
EDIT 2: Here is the entire error response I get when I attempt to call the web api route using Fiddler
{"message":"An error has occurred.","exceptionMessage":"An error
occurred when trying to create a controller of type 'Controller'. Make
sure that the controller has a parameterless public
constructor.","exceptionType":"System.InvalidOperationException","stackTrace":"
at
System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage
request, HttpControllerDescriptor controllerDescriptor, Type
controllerType) at
System.Web.Http.Controllers.HttpControllerDescriptor.CreateController(HttpRequestMessage
request) at
System.Web.Http.Dispatcher.HttpControllerDispatcher.d__1.MoveNext()","innerException":{"message":"An
error has occurred.","exceptionMessage":"Type 'Project.Controller'
does not have a default
constructor","exceptionType":"System.ArgumentException","stackTrace":"
at System.Linq.Expressions.Expression.New(Type type) at
System.Web.Http.Internal.TypeActivator.Create[TBase](Type
instanceType) 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)"}}
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