Dependency Injection asp.net core without constructor

Question

I have written a class like below

public sealed class SomeAttribute : Attribute, IResultFilter
{ 
   private INotificationhub notificationHub;
   public void OnResultExecuting(ResultExecutingContect filterContext)
   {

     //Need to set value notificationHub by resolving dependency

    //some other logic here


   }

}

in ConfigureServices of asp.net core

I have written

services.AddSingleton<INotificationHub, NotificationHub>();

How can I resolve the dependecy in the attribute class. I cannot do a constructor injection.

This link may be of use, to demonstrate how to inject dependencies action filters. A similar use case as yours. https://www.devtrends.co.uk/blog/dependency-injection-in-action-filters-in-asp.net-core — Tejas Parnerkar, Oct 06 '20 at 05:38

Athanasios Kataras · Accepted Answer · 2020-10-06T06:24:44.463

2

Does the following work for you:

public sealed class SomeAttribute : Attribute, IResultFilter
{ 
   private INotificationhub notificationHub;
   public void OnResultExecuting(ResultExecutingContect filterContext)
   {

     //Need to set value notificationHub by resolving dependency
    notificationHub = filterContext.HttpContext.RequestServices.GetService<INotificationhub>();

        // …
    //some other logic here


   }

}

Excellent article here, explaining this and other options: https://www.devtrends.co.uk/blog/dependency-injection-in-action-filters-in-asp.net-core

edited Oct 06 '20 at 06:24

answered Oct 06 '20 at 05:34

Athanasios Kataras

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Where is the article?I will try out the code provided by you and let you know – user3048027 Oct 06 '20 at 06:23
Sorry missed it during edit. – Athanasios Kataras Oct 06 '20 at 06:24

Dependency Injection asp.net core without constructor

1 Answers1