ASP.NET MVC Interim Released

The ASP.NET MVC Team has released an refresh of MVC. To all those that are interested the new Interim Release is posted at:

http://www.codeplex.com/aspnet/Release/ProjectReleases.aspx?ReleaseId=12640

The new release seems to rely on a non-CodePlex open source project.  Is this the first sign of Microsoft’s commitment to open source?

• http://code.google.com/p/moq/

The Release Notes have a lot of good information about new features and bug fixed included in this release:

This CodePlex refresh of the ASP.NET MVC source code includes a number of key changes and refactorings.
To see a full list of API changes, take a look at the attached zip file produced using
Framework Design Studio.

MVC Changes Since Preview 2

• Action methods on Controllers now by default return an ActionResult instance, instead of void.

  • This ActionResult object indicates the result from an action (a view to render, a URL to redirect to, another action/route to execute, etc).
  • Each “result” is a type that inherits from ActionResult. To render a view, return a RenderViewResult instance.

• The RenderView(), RedirectToAction(), and Redirect() helper methods on the Controller base class now return typed ActionResult objects (which you can further manipulate or return back from action methods).

• The RenderView() helper method can now be called without having to explicitly pass in the name of the view template you want to render.

  • When you omit the template name the RenderView() method will by default use the name of the action method to determine the view template to render.
  • So calling RenderView() with no parameters inside the About() action method is now the same as explicitly writing RenderView(‘About’).

• Introduced a new IActionFilter interface for action filters. ActionFilterAttribute implements IActionFilter.

• Action Filters now have four methods they can implement representing four possible interception points.

  • OnActionExecuting which occurs just before the action method is called.
  • OnActionExecuted which occurs after the action method is called, but before the result is executed (aka before the view is rendered in common scenarios).
  • OnResultExecuting which occurs just before the result is executed (aka before the view is rendered in common scenarios).
  • OnResultExecuted which occurs after the result is executed (aka after the view is rendered in common scenarios).
  • NOTE: The OnResult* methods will not be called if an exception is not handled during the invoking of the OnAction* methods or the action method itself.

• Added a MapRoute extension method (extension on RouteCollection) for use in declaring MVC routes in a simpler fashion.

NOTE: It is pretty easy to update existing Controller classes built with Preview 2 to use this new pattern (just change void to ActionResult and add a return statement in front of any RenderView or RedirectToAction helper method calls).

Routing changes since Preview 2

• URLs may contain any literal (except for /) as a separator between URL parameters. For example, instead of {action}.{format} you can now have {action}-{format}. For more details on changes, see this post.
• Routing is ignored for files that exist on disk by default. This can be overriden by setting the RouteTable.Routes.RouteExistingFiles property to true (it is false by default).