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asp.net mvc 2 - HttpHandler Property Injection using Ninject returning null

I have the following httphandler:

public class NewHandler : IHttpHandler
{
    [Inject]
    public IFile FileReader
    {
        get;
        set;
    }

    public NewHandler()
    {
    }

    public void ProcessRequest(System.Web.HttpContext context)
    {
        ....
        var something = SomeMethod(FileReader);
        ....
    }

    public bool IsReusable
    {
        get
        {
            return true;
        }
    }
}

This is my Ninject Module in the Global.asax.

internal class ServiceModule : NinjectModule
{
    public override void Load()
    {
        Bind<IFile>().To<FileWrapper>().InSingletonScope();
    }
}

Every time the handler fires the FileReader is NULL. Am I missing something? Is this the correct way to do property injection using Ninject?

Thanks

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1 Answer

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by (71.8m points)

This is the correct way to do property injection with Ninject, but it won't work. You are probably using something like NinjectMvcApplication class as a base class for you application, that handles dependency injection for controllers and everything controllers might use (services, repositories). But HttpHandlers are not instantiated by the ControllerFactory so nothing takes care of injecting stuff.

Maybe there's better way to do it, but i used service locator to resolve the dependency. See http://code.dortikum.net/2010/08/05/asp-net-mvc-di-with-common-service-locator-and-ninject/.

UPDATE:

Try something like this:

public class NewHandler : IHttpHandler
{
    private readonly IFile _fileReader;

    public NewHandler()
    {
        _fileReader = ServiceLocator.Current.GetInstance<IFile>();
    }

    public void ProcessRequest(System.Web.HttpContext context)
    {
        ....
        var something = SomeMethod(_fileReader);
        ....
    }

    public bool IsReusable
    {
        get
        {
            return true;
        }
    }
}

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