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copied!<p>Yes, there are downsides, as there are <a href="https://stackoverflow.com/questions/5653783/is-idependencyresolver-an-anti-pattern/5654204#5654204">lots of issues with IDependencyResolver</a> itself, and to those you can add the use of a <a href="https://stackoverflow.com/questions/137975/what-is-so-bad-about-singletons">Singleton</a> Service Locator, as well as <a href="https://stackoverflow.com/questions/7099406/what-is-the-real-difference-between-bastard-injection-and-poor-mans-injection">Bastard Injection</a>.</p> <p>A better option is to implement the filter as a normal class into which you can inject whichever services you'd like:</p> <pre><code>public class MyActionFilter : IActionFilter { private readonly IMyService myService; public MyActionFilter(IMyService myService) { this.myService = myService; } public void OnActionExecuting(ActionExecutingContext filterContext) { if(this.ApplyBehavior(filterContext)) this.myService.DoSomething(); } public void OnActionExecuted(ActionExecutedContext filterContext) { if(this.ApplyBehavior(filterContext)) this.myService.DoSomething(); } private bool ApplyBehavior(ActionExecutingContext filterContext) { // Look for a marker attribute in the filterContext or use some other rule // to determine whether or not to apply the behavior. } private bool ApplyBehavior(ActionExecutedContext filterContext) { // Same as above } } </code></pre> <p>Notice how the filter examines the filterContext to determine whether or not the behavior should be applied.</p> <p>This means that you can still use attributes to control whether or not the filter should be applied:</p> <pre><code>public class MyActionFilterAttribute : Attribute { } </code></pre> <p>However, now that attribute is completely inert.</p> <p>The filter can be composed with the required dependency and added to the global filters in global.asax:</p> <pre><code>GlobalFilters.Filters.Add(new MyActionFilter(new MyService())); </code></pre> <hr> <p>For a more detailed example of this technique, although applied to ASP.NET Web API instead of MVC, see this article: <a href="http://blog.ploeh.dk/2014/06/13/passive-attributes" rel="noreferrer">http://blog.ploeh.dk/2014/06/13/passive-attributes</a></p>

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