Asp.Net MVC Framework Design Pattern

The ASP.NET MVC Framework

Sarang Datyesarang.datye@microsoft.comhttp://www.dotnetbetaworks.com

ASP.NET MVC is…

A new Web Project Type for ASP.NET.

An option.

More control over your <html/>

A more easily Testable Framework.

Not for everyone.

What’s the Point?This is not Web Forms 4.0

It’s about alternatives. Car vs. Motorcycle.

Flexible

Extend it. Or not.

Fundamental

Part of System.Web and isn’t going anywhere.

Plays Well With Others

Feel free to use NHibernate for Models, Brail for Views and Whatever for Controllers.

Keep it simple and DRY

Goodness – Driving Goals

Maintain Clean Separation of Concerns

Easy Testing

Red/Green TDD

Highly maintainable applications by default

Extensible and Pluggable

Support replacing any component of the system

Goodness – Driving Goals

Enable clean URLs and HTML

SEO and REST friendly URL structures

Great integration within ASP.NET

All the same providers still work

Membership, Session, Caching, etc.

ASP.NET Designer Surface in VS2008

MVC

Model

ControllerView

A Little More Detail

Model

ControllerView

•Browser requests /Products/

•Route is determined

•Controller is activated

•Method on Controller is invoke

•Controller does some stuff

•Renders View, passing in

custom ViewData

•URLs are rendered,

pointing to other

Controllers

Even More Detail – Request Flow

• You can futz at each step

in the processRequest

HTTPRouting

RouteRoute

Handler

HttpHandler

Controller

ViewEngine View

Response

ExtensibilityViews

Controllers

Models

Routes

…are all Pluggable

Demo – Complete Application

It’s your thing. Do what you wanna do.

What’s the Point?This is not Web Forms 4.0

It’s about alternatives. Car vs. Motorcycle.

Flexible

Extend it. Or not.

Fundamental

Part of System.Web and isn’t going anywhere.

Plays Well With Others

Feel free to use NHibernate for Models, Brail for Views and Whatever for Controllers.

Keep it simple and DRY

URL Routing – Pretty URIsDevelopers adds 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 {

{"year", @"\d{1.4}"},

{"month", @"\d{1.2}"},

{"day", @"\d{1.2}"}}

})

Testing Controller Actions

No requirement to test within ASP.NET runtime.Use RhinoMocks or TypeMock

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);

}

Controller

Base Controller Class

Basic Functionality most folks will use

IController Interface

Ultimate Control for the Control Freak

IControllerFactory

For plugging in your own stuff (IOC, etc)

Basic Controller HandlingScenarios, Goals and Design

URLs route to controller “actions”, not pages –mark actions in Controller.

Controller executes logic, chooses view.

All public methods are accessible

public void ShowPost(int id) {Post p = PostRepository.GetPostById(id);if (p != null) {

RenderView("showpost", p);} else {

RenderView("nosuchpost", id);}

}

Controller Base Classpublic class Controller : IController {

…

protected virtual void Execute(ControllerContextcontrollerContext);

protected virtual void HandleUnknownAction(string actionName);

protected virtual bool InvokeAction(string actionName);

protected virtual void InvokeActionMethod(MethodInfo methodInfo);

protected virtual bool OnError(string actionName,

MethodInfo methodInfo, Exception exception);

protected virtual void OnActionExecuted(FilterExecutedContextfilterContext);

protected virtual bool OnActionExecuting(FilterExecutedContextfilterContext);

protected virtual void RedirectToAction(object values);

protected virtual void RenderView(string viewName,

string masterName, object viewData);

}

Controller – Regular APIspublic class Controller : IController {

…

protected virtual void Execute(ControllerContextcontrollerContext);

protected virtual void HandleUnknownAction(string actionName);

protected virtual bool InvokeAction(string actionName);

protected virtual void InvokeActionMethod(MethodInfo methodInfo);

protected virtual bool OnError(string actionName,

MethodInfo methodInfo, Exception exception);

protected virtual void OnActionExecuted(FilterExecutedContextfilterContext);

protected virtual bool OnActionExecuting(FilterExecutedContextfilterContext);

protected virtual void RedirectToAction(object values);

protected virtual void RenderView(string viewName,

string masterName, object viewData);

}

Controller – Customization APIspublic class Controller : IController {

…

protected virtual void Execute(ControllerContextcontrollerContext);

protected virtual void HandleUnknownAction(string actionName);

protected virtual bool InvokeAction(string actionName);

protected virtual void InvokeActionMethod(MethodInfo methodInfo);

protected virtual bool OnError(string actionName,

MethodInfo methodInfo, Exception exception);

protected virtual void OnActionExecuted(FilterExecutedContextfilterContext);

protected virtual bool OnActionExecuting(FilterExecutedContextfilterContext);

protected virtual void RedirectToAction(object values);

protected virtual void RenderView(string viewName,

string masterName, object viewData);

}

Controller – Test Hookspublic class Controller : IController {

…

protected virtual void Execute(ControllerContextcontrollerContext);

protected virtual void HandleUnknownAction(string actionName);

protected virtual bool InvokeAction(string actionName);

protected virtual void InvokeActionMethod(MethodInfo methodInfo);

protected virtual bool OnError(string actionName,

MethodInfo methodInfo, Exception exception);

protected virtual void OnActionExecuted(FilterExecutedContextfilterContext);

protected virtual bool OnActionExecuting(FilterExecutedContextfilterContext);

protected virtual void RedirectToAction(object values);

protected virtual void RenderView(string viewName,

string masterName, object viewData);

}

© 2008 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.

The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market

conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation.

MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.