Question

Following on from another question I had here I’ve got a MainConfig object and I want to inject certain properties of that object instead of the actual MainConfig object itself. Excerpt from my module Load method:

Bind<IConfig>()
    .ToMethod<IConfig>(ctx => MainConfig.Load())
    .InSingletonScope();

var config = Kernel.Get<IConfig>(); //this returns a fully-loaded IConfig, so I know this works

Bind<IProcessingBuffer>()
    .To<ProcessingBuffer>()
    .InSingletonScope()
    .WithConstructorArgument("processingInterval",
                             ctx => ctx.Kernel.Get<IConfig>().WinService.DataProcessingInterval);

The constructor for ProcessingBuffer is:

public ProcessingBuffer(int processingInterval, IProcessingResults procResults)

However, when I try to start my application I get an ActivationException because the processingInterval isn’t being injected into the ProcessingBuffer. The exception is:

Ninject.ActivationException was unhandled
  Message=Error activating int
No matching bindings are available, and the type is not self-bindable.
Activation path:
  5) Injection of dependency int into parameter processingInterval of constructor of type ProcessingBuffer
  4) Injection of dependency ProcessingBuffer into parameter procBuffer of constructor of type MyCompanyDataService
  3) Injection of dependency MyCompanyDataService into parameter instance of constructor of type NinjectServiceHost{MyCompanyDataService}
  2) Injection of dependency NinjectServiceHost{MyCompanyDataService} into parameter dataHost of constructor of type MyCompanyWinService
  1) Request for MyCompanyWinService

Suggestions:
  1) Ensure that you have defined a binding for int.
  2) If the binding was defined in a module, ensure that the module has been loaded into the kernel.
  3) Ensure you have not accidentally created more than one kernel.
  4) If you are using constructor arguments, ensure that the parameter name matches the constructors parameter name.
  5) If you are using automatic module loading, ensure the search path and filters are correct.

  Source=Ninject
  StackTrace:
       at Ninject.KernelBase.Resolve(IRequest request) in c:\Projects\Ninject\ninject\src\Ninject\KernelBase.cs:line 362
       at Ninject.Planning.Targets.Target`1.GetValue(Type service, IContext parent) in c:\Projects\Ninject\ninject\src\Ninject\Planning\Targets\Target.cs:line 197
       at Ninject.Planning.Targets.Target`1.ResolveWithin(IContext parent) in c:\Projects\Ninject\ninject\src\Ninject\Planning\Targets\Target.cs:line 165
       at Ninject.Activation.Providers.StandardProvider.GetValue(IContext context, ITarget target) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\StandardProvider.cs:line 114
       at Ninject.Activation.Providers.StandardProvider.<>c__DisplayClass4.<Create>b__2(ITarget target) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\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 c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\StandardProvider.cs:line 96
       at Ninject.Activation.Context.Resolve() in c:\Projects\Ninject\ninject\src\Ninject\Activation\Context.cs:line 157
       at Ninject.KernelBase.<>c__DisplayClass10.<Resolve>b__c(IBinding binding) in c:\Projects\Ninject\ninject\src\Ninject\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 c:\Projects\Ninject\ninject\src\Ninject\Planning\Targets\Target.cs:line 197
       at Ninject.Planning.Targets.Target`1.ResolveWithin(IContext parent) in c:\Projects\Ninject\ninject\src\Ninject\Planning\Targets\Target.cs:line 165
       at Ninject.Activation.Providers.StandardProvider.GetValue(IContext context, ITarget target) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\StandardProvider.cs:line 114
       at Ninject.Activation.Providers.StandardProvider.<>c__DisplayClass4.<Create>b__2(ITarget target) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\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 c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\StandardProvider.cs:line 96
       at Ninject.Activation.Context.Resolve() in c:\Projects\Ninject\ninject\src\Ninject\Activation\Context.cs:line 157
       at Ninject.KernelBase.<>c__DisplayClass10.<Resolve>b__c(IBinding binding) in c:\Projects\Ninject\ninject\src\Ninject\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 c:\Projects\Ninject\ninject\src\Ninject\Planning\Targets\Target.cs:line 197
       at Ninject.Planning.Targets.Target`1.ResolveWithin(IContext parent) in c:\Projects\Ninject\ninject\src\Ninject\Planning\Targets\Target.cs:line 165
       at Ninject.Activation.Providers.StandardProvider.GetValue(IContext context, ITarget target) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\StandardProvider.cs:line 114
       at Ninject.Activation.Providers.StandardProvider.<>c__DisplayClass4.<Create>b__2(ITarget target) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\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 c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\StandardProvider.cs:line 96
       at Ninject.Activation.Context.Resolve() in c:\Projects\Ninject\ninject\src\Ninject\Activation\Context.cs:line 157
       at Ninject.KernelBase.<>c__DisplayClass10.<Resolve>b__c(IBinding binding) in c:\Projects\Ninject\ninject\src\Ninject\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 c:\Projects\Ninject\ninject\src\Ninject\Planning\Targets\Target.cs:line 197
       at Ninject.Planning.Targets.Target`1.ResolveWithin(IContext parent) in c:\Projects\Ninject\ninject\src\Ninject\Planning\Targets\Target.cs:line 165
       at Ninject.Activation.Providers.StandardProvider.GetValue(IContext context, ITarget target) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\StandardProvider.cs:line 114
       at Ninject.Activation.Providers.StandardProvider.<>c__DisplayClass4.<Create>b__2(ITarget target) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\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 c:\Projects\Ninject\ninject\src\Ninject\Activation\Providers\StandardProvider.cs:line 96
       at Ninject.Activation.Context.Resolve() in c:\Projects\Ninject\ninject\src\Ninject\Activation\Context.cs:line 157
       at Ninject.KernelBase.<>c__DisplayClass10.<Resolve>b__c(IBinding binding) in c:\Projects\Ninject\ninject\src\Ninject\KernelBase.cs:line 386
       at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
       at System.Linq.Enumerable.<CastIterator>d__b1`1.MoveNext()
       at System.Linq.Enumerable.Single[TSource](IEnumerable`1 source)
       at Ninject.ResolutionExtensions.Get[T](IResolutionRoot root, IParameter[] parameters) in c:\Projects\Ninject\ninject\src\Ninject\Syntax\ResolutionExtensions.cs:line 37
       at MyCompany.WinService.Program.Main(String[] args) in C:\Projects\MyProject\MyCompanyWinService\Program.cs:line 41
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: 

Is there any way I can confirm that my WithConstructorArgument lambda is even being called and then trace it through? I’ve downloaded the Ninject source but I can’t work out where to set the breakpoint to find where my callback is used.

The application is a Windows Service that uses Ninject 3.0 and Ninject.Extensions.Wcf to host a WCF TCP service.

Edit to add: If I change the ProcessingBuffer constructor to take the entire IConfig object and remove the WithConstructorArgument call then the IConfig object is injected successfully and I can access the appropriate property. However, I want to move away from injecting the entire IConfig object to remove the dependency and instead only pass in the required data.

Answer 1

Your MyCompanyDataService takes an instance of ProcessingBuffer not IProcessingBuffer. Therefore your binding does not apply.