Working with built-in dependency injection of ASP .NET Core - finding and adding to container

AttributeInjector.cs

public static class AttributeInjector
{
    public static void AddInjectionByAttribute(this IServiceCollection services)
    {
        RegisterWithAttribute(ref services, typeof(InjectableSingletonAttribute));
        RegisterWithAttribute(ref services, typeof(InjectableTransientAttribute));
        RegisterWithAttribute(ref services, typeof(InjectableScopedAttribute));
    }

    private static void RegisterWithAttribute(ref IServiceCollection services, Type injectableAttribute)
    {
        foreach(var assembly in AppDomain.CurrentDomain.GetAssemblies())
        {
            var allTypes = assembly.GetTypes();

            var classesWithAttribute = allTypes.Where(t => t.IsClass && t.CustomAttributes.Any(a => a.AttributeType == injectableAttribute));

            var an = classesWithAttribute.ToArray();

            foreach (var implementationType in classesWithAttribute)
            {
                var interfaceType = allTypes.FirstOrDefault(t => t.IsInterface && t.Name.Substring(1) == implementationType.Name);

                if (interfaceType == null) throw new Exception($"Failed to resolve interface for class {implementationType.Name}, unable to inject dependency!");

                if (injectableAttribute == typeof(InjectableTransientAttribute))
                    services.AddTransient(interfaceType, implementationType);
                if (injectableAttribute == typeof(InjectableScopedAttribute))
                    services.AddScoped(interfaceType, implementationType);
                if (injectableAttribute == typeof(InjectableSingletonAttribute))
                    services.AddSingleton(interfaceType, implementationType);
            }
        }            
    }
}