--- title: ASP.NET MVC 3 and MEF sitting in a tree... | daily.dev description: A walkthrough of implementing dependency injection in ASP.NET MVC 3 preview 1 using the Managed Extensibility Framework (MEF). The post explains the new... canonical: https://daily.dev/posts/asp-net-mvc-3-and-mef-sitting-in-a-tree--3v6kaoy7w twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: ASP.NET MVC 3 and MEF sitting in a tree... | daily.dev og:description: A walkthrough of implementing dependency injection in ASP.NET MVC 3 preview 1 using the Managed Extensibility Framework (MEF). The post explains the new... og:url: https://daily.dev/posts/asp-net-mvc-3-and-mef-sitting-in-a-tree--3v6kaoy7w og:image: https://api.daily.dev/og/posts/3v6kAoY7W.png og:image:alt: ASP.NET MVC 3 and MEF sitting in a tree... og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # ASP.NET MVC 3 and MEF sitting in a tree... **[Maarten Balliauw](https://daily.dev/sources/maartenballiauw)** · 7 min read · 0 upvotes · 0 comments ## Summary A walkthrough of implementing dependency injection in ASP.NET MVC 3 preview 1 using the Managed Extensibility Framework (MEF). The post explains the new IServiceLocator-based DI hooks introduced in MVC 3 (controller factories, controller creation, view creation, action filters) and shows full code for a custom ServiceLocatorControllerFactory and MefServiceLocator that compose controllers and views via MEF, with a fallback to the default locator for framework services not exported via MEF. Sample code is provided for download. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How do I set up dependency injection in ASP.NET MVC 3 using the new IServiceLocator? Register an IServiceLocator implementation in Global.asax with a single call: MvcServiceLocator.SetCurrent(new SomeServiceLocator()). This makes dependency injection work automatically across controllers, action filters, and views, since ASP.NET MVC 3 preview 1 routes its four new DI hooks (controller factories, controllers, views, action filters) through the Common Service Locator's IServiceLocator interface. _daily.dev surfaces practical deep dives like this for developers wiring DI into ASP.NET MVC._ ### How can I use MEF (Managed Extensibility Framework) to compose controllers and views in ASP.NET MVC? Build a custom IMvcServiceLocator backed by a MEF CompositionContainer, plus a ServiceLocatorControllerFactory that resolves controllers through that locator instead of DefaultControllerFactory. Export controller types with [Export], use a per-request container with an application-wide catalog, and fall back to the default MVC service locator for framework types like IFilterProvider that aren't MEF-exported. _developers piecing together MEF-based composition can find similar in-depth examples on daily.dev._ ## Similar posts on daily.dev - [12 Rules for Dependency Injection in ASP.NET Core](https://daily.dev/posts/12-rules-for-dependency-injection-in-asp-net-core-nirfrs5ef) · We Are .NET · 3 upvotes · 1 comments - [How to Migrate from ASP.NET Framework to ASP.NET Core](https://daily.dev/posts/how-to-migrate-from-asp-net-framework-to-asp-net-core-e22ntd3va) · freeCodeCamp · 4 upvotes · 0 comments - [ASP.NET, Factory Patterns, and the Illusion of Control](https://daily.dev/posts/asp-net-factory-patterns-and-the-illusion-of-control-up6aoiahc) · We Are .NET · 3 upvotes · 0 comments - [How to Upgrade ASP.NET MVC to .NET Step by Step](https://daily.dev/posts/how-to-upgrade-asp-net-mvc-to-net-step-by-step-i3p1uesfs) · C\# Corner · 2 upvotes · 0 comments --- Tags: [#aspnet](https://daily.dev/tags/aspnet), [#c#](https://daily.dev/tags/c#), [#dependency-injection](https://daily.dev/tags/dependency-injection) [View this post on daily.dev](https://daily.dev/posts/asp-net-mvc-3-and-mef-sitting-in-a-tree--3v6kaoy7w) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"ASP.NET MVC 3 and MEF sitting in a tree...","url":"https://daily.dev/posts/asp-net-mvc-3-and-mef-sitting-in-a-tree--3v6kaoy7w","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/asp-net-mvc-3-and-mef-sitting-in-a-tree--3v6kaoy7w"},"datePublished":"2026-10-04T13:05:57.405Z","dateModified":"2026-10-15T02:22:30.608Z","description":"A walkthrough of implementing dependency injection in ASP.NET MVC 3 preview 1 using the Managed Extensibility Framework (MEF). 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