Ninject for Web Api 2 is not working in ASP.NET MVC -

i developing asp.net mvc application. in application, need provide rest api. added web api 2 existing mvc application. before added web api 2, using ninject dependency injection. installed via nuget package. whole website developed , working. problem started when added web api 2 project. ninject mvc cannot used web api. installed ninject web api 2. ninjectwebcommon class has been changed after installed it.

this ninjectwebcommon file in app_start folder

[assembly: webactivatorex.preapplicationstartmethod(typeof(ayardirectory.web.app_start.ninjectwebcommon), "start")] [assembly: webactivatorex.applicationshutdownmethodattribute(typeof(ayardirectory.web.app_start.ninjectwebcommon), "stop")]  namespace ayardirectory.web.app_start {     using system;     using system.web;      using microsoft.web.infrastructure.dynamicmodulehelper;      using ninject;     using ninject.web.common;      public static class ninjectwebcommon      {         private static readonly bootstrapper bootstrapper = new bootstrapper();          /// <summary>         /// starts application         /// </summary>         public static void start()          {             dynamicmoduleutility.registermodule(typeof(oneperrequesthttpmodule));             dynamicmoduleutility.registermodule(typeof(ninjecthttpmodule));             bootstrapper.initialize(createkernel);         }          /// <summary>         /// stops application.         /// </summary>         public static void stop()         {             bootstrapper.shutdown();         }          /// <summary>         /// creates kernel manage application.         /// </summary>         /// <returns>the created kernel.</returns>         private static ikernel createkernel()         {             var kernel = new standardkernel();             try             {                 kernel.bind<func<ikernel>>().tomethod(ctx => () => new bootstrapper().kernel);                 kernel.bind<ihttpmodule>().to<httpapplicationinitializationhttpmodule>();                  registerservices(kernel);                 return kernel;             }             catch             {                 kernel.dispose();                 throw;             }         }          /// <summary>         /// load modules or register services here!         /// </summary>         /// <param name="kernel">the kernel.</param>         private static void registerservices(ikernel kernel)         {             system.web.mvc.dependencyresolver.setresolver(new ayardirectory.web.infrastructure.ninjectdependencyresolver(kernel));         }             } } 

i changed place after installed ninject web api 2.then run application. website working fine. website still working. web api not working.

this resolver class

namespace ayardirectory.web.infrastructure {     public class ninjectdependencyresolver : idependencyresolver     {         private ikernel kernel;          public ninjectdependencyresolver(ikernel kernelparam)         {             kernel = kernelparam;             addbindings();         }          public object getservice(type servicetype)         {             return kernel.tryget(servicetype);         }          public ienumerable<object> getservices(type servicetype)         {             return kernel.getall(servicetype);         }          private void addbindings()         {             kernel.bind<icategoryrepo>().to<categoryrepo>();          }     } } 

i dependency injection in api controller this

public class regionscontroller : apicontroller     {         private iregionrepo regionrepo;          private regionscontroller(iregionrepo regionparam)         {             this.regionrepo = regionparam;         }          . . . } 

when access 1 of action of api controller, giving me following error.

{"message":"an error has occurred.","exceptionmessage":"an error occurred when trying create controller of type 'regionscontroller'. make sure controller has parameterless public constructor.","exceptiontype":"system.invalidoperationexception","stacktrace":"   @ system.web.http.dispatcher.defaulthttpcontrolleractivator.create(httprequestmessage request, httpcontrollerdescriptor controllerdescriptor, type controllertype)\r\n   @ system.web.http.controllers.httpcontrollerdescriptor.createcontroller(httprequestmessage request)\r\n   @ system.web.http.dispatcher.httpcontrollerdispatcher.sendasynccore(httprequestmessage request, cancellationtoken cancellationtoken)\r\n   @ system.web.http.dispatcher.httpcontrollerdispatcher.<sendasync>d__0.movenext()","innerexception":{"message":"an error has occurred.","exceptionmessage":"type 'ayardirectory.web.controllers.api.regionscontroller' not have default constructor","exceptiontype":"system.argumentexception","stacktrace":"   @ system.linq.expressions.expression.new(type type)\r\n   @ system.web.http.internal.typeactivator.create[tbase](type instancetype)\r\n   @ system.web.http.dispatcher.defaulthttpcontrolleractivator.getinstanceoractivator(httprequestmessage request, type controllertype, func`1& activator)\r\n   @ system.web.http.dispatcher.defaulthttpcontrolleractivator.create(httprequestmessage request, httpcontrollerdescriptor controllerdescriptor, type controllertype)"}} 

so please, why not working? missing or wrong code? please how can fix it? how can use ninject web api 2 please? using mvc 5.