Jess Chadwick Website Manager, Infragistics

The Genealogy of Awesomeness History of Microsoft Web Stuff

Active Server Pages

Active Server Pages (ASP)  V1 circa 1996  “Active Scripting Pages”: top-down script  Call into VB6/COM code to do “real work”  You might remember these oldies but goodies:  Request object  Response object  Session object  Server object  Application object  ObjectContext object  ASPError object

Classic ASP Example

ASP.NET  Released in 2002 as part of.NET 1.0  Not “ASP v.Next” – completely new  Introduced a few important concepts:  Rich programming framework  Code-Behind  Page Lifecycle  The omnipresent ViewState !

ASP.NET Page Lifecycle

“ASP.NET Extensions”  Started with “ASP.NET Futures”  ASP.NET AJAX  Silverlight Controls  ADO.NET Data Services  ASP.NET Dynamic Data And…  ASP.NET MVC!

What is ASP.NET MVC?  Microsoft’s ASP.NET implementation of the MVC software pattern  More control over your HTML and URLs  More easily testable framework  A new Web Project type for ASP.NET  An option / alternative

Let’s whet the appetite! DEMO: MVC Hello World

What’s the Point?  This is not “Web Forms v.Next”  All about alternatives  Flexibility  Extend it… or not  Create your own Controller- and ViewEngines, or use others such as Brail or NHaml  Fundamental  Part of System.Web namespace  Fully supported  KISS & DRY

Driving Goals  Separation of Concerns  Easy testing & TDD  Highly-maintainable applications  Extensible and Pluggable  Plug in what you need  Build your own custom build

Driving Goals (cont’d)  Clean URLs and HTML  SEO and REST friendly  Great interaction with ASP.NET  Handlers, Modules, Providers, etc. still work .ASPX,.ASCX,.MASTER pages  Visual Studio ASP.NET Designer surface

Careful – there’s a grease spot over there… Take a Look Under the Hood

Request Flow Request HTTP Routing Route Route Handler Http Handler Controller View Engine View Response

The Pattern ModelController View

The Model “The center of the universe” - Todd Snyder  This represents your core business domain… AKA – your “bread and butter”  Preferably independent of any specific technology

Views  Are for rendering/output.  Are usually pretty “stupid”  Web Forms as default ViewEngine .ASPX,.ASCX,.MASTER, etc.  Html Helpers for rendering markup  Can replace with other view technologies:  Template engines (NVelocity, Brail, …).  Output formats (images, RSS, JSON, …).  Mock out for testing.  Can use loosely typed or strongly typed data

Controllers  URLs route to actions on controllers, not pages  Controller executes logic, loads data (if any), and chooses view.  Can also redirect to other views & URLs public ActionResult ShowPost(int id) { Post p = PostRepository.GetPostById(id); if (p == null) { return RenderView("nosuchpost", id); } else { return RenderView(“showpost", p); }

Request Flow Request HTTP Routing Route Route Handler Http Handler Controller View Engine View Response

ModelController View The MVC Pattern in action Browser makes a request Route is determined Controller is activated Method on Controller is invoked Controller does some stuff Renders View, passing in custom ViewData URLs are rendered, pointing to other Controllers

DEMO: Northwind Sample

Routing Filters Extensibility View Engines Controller Factories Routing Handler ASP.NET MVC Features

URL Routing  Developers add Routes to a global RouteTable  Mapping creates a RouteData - a bag of key/values RouteTable.Routes.Add( new Route("blog/bydate/{year}/{month}/{day}", new MvcRouteHandler()){ Defaults = new RouteValueDictionary { {"controller", "blog"}, {"action", "show"} }, Constraints = new RouteValueDictionary { })

“Can’t you just stop and ask for directions!?” Demo: URL Routing

URL Routing (cont’d)  Separate assembly, not closely tied/related to ASP.NET MVC

Filters  Add pre- and post-execute behaviors to your controller actions  Useful for logging, compression, etc. public abstract class ActionFilterAttribute { public void OnActionExecuting(ActionExecutingContext context) ; public void OnActionExecuted(ActionExecutingContext context) ; // New in Pre-Preview 3: public void OnResultExecuting(ResultExecutingContext context); public void OnResultExecuted(ResultExecutedContext context); }

Extensibility  Views  Controllers  Models  Routes …all Pluggable

ViewEngineBase  View Engines render output  You get WebForms by default  Can implement your own  MVCContrib has ones for Brail, Nvelocity  NHaml is an interesting one to watch  View Engines can be used to  Offer new DSLs to make HTML easier  Generate totally different mime/types  Images, RSS, JSON, XML, OFX, VCards, whatever.

ViewEngineBase Class public abstract class ViewEngineBase { public abstract void RenderView(ViewContext viewContext); }

Example View: Web Forms Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master" AutoEventWireup="true" CodeBehind="List.aspx" Inherits="MvcApplication5.Views.Products.List" Title="Products" %> CodeBehind="List.aspx" Inherits="MvcApplication5.Views.Products.List" Title="Products" %> ( ) ( ) </asp:Content>

Example View: NHaml %h2= ViewData.CategoryName %ul - foreach (var product in ViewData.Products) %li = product.ProductName.editlink = Html.ActionLink("Edit", new { Action="Edit", ID=product.ProductID }) = Html.ActionLink("Add New Product", new { Action="New" }) - foreach (var product in ViewData.Products) %li = product.ProductName.editlink = Html.ActionLink("Edit", new { Action="Edit", ID=product.ProductID }) = Html.ActionLink("Add New Product", new { Action="New" })

Now we can really take control! Demo: Filters and View Engines

MVCContrib  Myriad UI helper extensions and classes  View Engines  NHaml  NVelocity  Brail  Xslt  Controller factories (for IoC)  Castle (Windsor)  Spring.NET  Ninject  StructureMap  Object Builder  Unity Open Source project with extensions to base framework On CodePlex at

“What!? I can mock out HttpContext!?” Testability

Designed for Testability  Mockable Intrinsics  HttpContextBase, HttpResponseBase, HttpRequestBase  Extensibility  IController  IControllerFactory  IRouteHandler  ViewEngineBase

Testing Controller Actions  No requirement to test within ASP.NET runtime!  Use RhinoMocks, TypeMock, Moq, etc.  Create Test versions of the parts of the runtime you want to stub [TestMethod] public void ShowPostsDisplayPostView() { TestPostRepository repository = new TestPostRepository(); TestViewEngine viewEngine = new TestViewEngine(); BlogController controller = new BlogController(…); controller.ShowPost(2); Assert.AreEqual("showpost",viewEngine.LastRequestedView); Assert.IsTrue(repository.GetPostByIdWasCalled); Assert.AreEqual(2, repository.LastRequestedPostId); } [TestMethod] public void ShowPostsDisplayPostView() { TestPostRepository repository = new TestPostRepository(); TestViewEngine viewEngine = new TestViewEngine(); BlogController controller = new BlogController(…); controller.ShowPost(2); Assert.AreEqual("showpost",viewEngine.LastRequestedView); Assert.IsTrue(repository.GetPostByIdWasCalled); Assert.AreEqual(2, repository.LastRequestedPostId); }

“Wasn’t this supposed to come first?” DEMO: Test-Driven Development

(I know what you’re thinking…) Popular Questions

Why reinvent the wheel?  Aren’t there already existing frameworks out there, such as Monorail?

ASP.NET MVC & REST  Does MVC do REST?  Depends on your definition.  What about ADO.NET Data Extensions (Astoria) and/or WCF?

Controls & Components  Can still use server controls?  Can we still use Web Forms server controls?  Decent support for user controls  Still more/better support to come

What about AJAX?  ASP.NET AJAX?  Requires  Roll your own  JS frameworks like jQuery make this easier

Scalability, Performance, Security, Etc.  A layer of abstraction working over the solid, tested ASP.NET foundation

When’s It Gonna Be Ready?

What’s the Point?  This is not “Web Forms v.Next”  All about alternatives  Flexibility  Extend it… or not  Create your own Controller- and ViewEngines, or use others such as Brail or NHaml  Fundamental  Part of System.Web namespace  Fully supported  KISS & DRY

Q & A (…and Thank You!)

Resources  The Bits  ASP.NET MVC Preview 2:  ASP.NET MVC Pre-Preview3:  MVCContrib:  Quickstart   Videos  ASP.NET:  MIX:  Community/Blogs  ASP.NET Forums:  Scott Guthrie (ScottGu):  Scott Hanselman:  Phil Haack:  Sample Apps  MVC Samples:  CodeCampServer: Jess Chadwick Web Lead Infragistics, Inc.