CustomKernel.cs

/// <summary>
/// Allows using <see cref="IInject{T}"/> and explicit implementation of interfacemethods with [Inject]
/// </summary>
public class CustomKernel : StandardKernel
{
    public CustomKernel(INinjectSettings settings, params INinjectModule[] modules)
        : base(settings, modules)
    {
    }

    protected override void AddComponents()
    {
        base.AddComponents();
        Components.Remove<ISelector, Selector>();
        Components.Add<ISelector, IInjectSelector>();
    }

    private class IInjectSelector : Selector
    {
        public IInjectSelector([NotNull] IConstructorScorer constructorScorer, [NotNull] IEnumerable<IInjectionHeuristic> injectionHeuristics)
            : base(constructorScorer, injectionHeuristics)
        {
        }

        /// <summary>
        /// Allows for:
        /// 1) Explicit implementation of methods with [Inject] attribute
        /// 2) Implementing <see cref="IInject{T}"/>
        /// </summary>
        /// <param name="type"></param>
        /// <returns></returns>
        public override IEnumerable<MethodInfo> SelectMethodsForInjection(Type type)
        {
            return base.SelectMethodsForInjection(type)
                       .Concat(type.GetInterfaces()
                                   .SelectMany(i => i.GetMethods().Where(m => m.IsDefined(typeof(InjectAttribute), true))))
                       .Concat(type.GetInterfaces()
                               .Where(x => x.IsGenericType && x.GetGenericTypeDefinition() == typeof(IInject<>))
                               .Select(type.GetInterfaceMap)
                               .SelectMany(im => im.InterfaceMethods));
        }
    }
}