1. Venketash (Pat) Ramadass
Systems Architect & Managing Director
emediaIT
pat.ramadass@emediait.com
http://patramadass.emediait.com

2. Separation of Concerns

MVC

ASP.NET MVC

Demonstrations of building simple ASP.NET

MVC functionality
Questions


3. Presentation logic, business logic and data

access logic are mixed together too often
 Business logic code within the User Interface
 Unmanagable code, goes against good OO
principles
Proper Separation of Concerns (SoC) solves

this by de-coupling the overall architecture

4. Stands for Model-View-Controller

It is a design pattern for software development

Designed to promote and enforce Separation

of Concerns
 Model – Data Access and Business Logic
 View – User Interface
 Controller – Handles User Interaction and Model
Manipulation

5. User
User Interface Generates Events
View(s) Controller(s)
Provides Data Manipulates
Model

6. MVC Framework which Microsoft is adding to

ASP.NET
Alternative to ASP.NET, not a replacement

Can combine both in a single solution

Currently in public beta, but there are

production systems using it already

7. Clear separation of concerns (SoC)

Testability - support for TDD

Fine-grained control over HTML and

JavaScript
Intuitive URLs (Routing) – SEO Friendly


8. Functionality Webforms ASP.NET MVC
URLs Page names and URL Routing Programmatically -
Rewriting REST
Event Driven Yes No
Stateful Yes (Viewstate) No
Easily Unit Tested No Yes
Abstraction from HTML Yes No
Exact control over HTML No Yes
Supports ORM Yes Yes
Easy use of Third Party UI Yes Partial (No state/postback
controls controls only)
Works on Linux/Mono Yes (Partial) Not yet supported, but can be
made to work
The above is not intended to be a complete list, it simply highlights some key differences.

9. 6
View
Routing
Controller
1 2 5
Rules
3
1. HTTP Request
2. ASP.NET MVC Framework evaluates URL against registered
Routing Rules and forwards the request to a matching Controller
Model Data Store
4
3. Controller calls Model to build ViewData, if required
4. The Model returns the requested Data to the Controller
5. The Controller selects a View and passes the Model to the View
6. View renders and returns HTTP Response

10. Creating a new MVC Project

Folder Structure

Sample application included in ASP.NET MVC

Application Template
A URL does not equal a page

Understanding URL Routing


11. URL: /Product/Details/3

 This URL is parsed into three parts like this:
▪ Controller = ProductController
▪ Action = Details
▪ Id = 3
 The request is therefore routed to the Details() action
on the ProductController class, with a Id parameter of
3
 Notice that the suffix Controller is tacked on to the
end of the Controller parameter.

12. Default Route

 Default Controller: HomeController
 Default Action: Index
 Default Id: Empty String
URL: /Employee

 This URL is parsed into three parts like this:
▪ Controller = EmployeeController
▪ Action = Index
▪ Id = “”
 The request is therefore routed to the Index() action on
the EmployeeController class

13. Default Route

 Default Controller: HomeController
 Default Action: Index
 Default Id: Empty String
URL: http://localhost, i.e. Without supplying a

further URL

14. In a blog application, you may want to handle

incoming requests that look like: /Archive/12-
25-2009. For this you would need a Custom
Route.
The order in which routes are added is

important

16. A controller should only contain the bare minimum of logic

required to return the right view or redirect the user to another
action.
A controller is just a Class, inherits from

System.Web.Mvc.Controller
HomeController.cs has 2 methods called Index() and About(),

these are the actions it exposes.
The URL /Home/Index invokes the HomeController.Index()

method and the URL /Home/About invokes the
HomeController.About() method.
Any public method in a controller is exposed as a controller

action.

17. A method used as a controller action cannot be overloaded or static

A controller action returns action result.

Six standard types of action results:

 ViewResult – Represents HTML and markup.
 EmptyResult – Represents no result.
 RedirectResult – Represents a redirection to a new URL.
 RedirectToRouteResult – Represents a redirection to a new controller action.
 JsonResult – Represents a JavaScript Object Notation result that can be used
in an AJAX application.
 ContentResult – Represents a text result.
ContentResult is useful for returning plain text such as dates, integers etc


18. Instead of returning an action result directly, you

normally call one of the following methods on
the Controller base class:
 View – Returns a ViewResult action result.
 Redirect – Returns a RedirectResult action result.
 RedirectToAction – Returns a RedirectToRouteResult
action result.
 RedirectToRoute – Returns a RedirectToRouteResult
action result.
 Json – Returns a JsonResult action result.
 Content – Returns a ContentResult action result.

19. Modifying ActionResult


20. A view should contain only logic related to generating the user

interface.
A view contains the HTML markup and content that is sent to the

browser. A view is the equivalent of a page.
In general, to return a view for a controller action, you must create

a subfolder in the Views folder with the same name as your
controller. Within the subfolder, you must create an .aspx file with
the same name as the controller action.
The HomeController.Index() action returns a view located at the

following path: ViewsHomeIndex.aspx
The HomeController.About() action returns a view located at the

following path: ViewsHomeAbout.aspx

21. Adding a new View Page

Using HTML Helpers to Generate View

Content
Using View Data to Pass Data to a View


22. An MVC model contains all of your

application logic that is not contained in a
view or a controller. This should be all of
your business logic and data access logic
Aim for fat models and skinny controllers


23. Create a new Database

Create a new Model

Using LINQ in Controller Actions

Using the Repository Pattern


24. Why TDD?

Testing the View returned by a Controller

Testing the View Data returned by a

Controller
Testing the Action Result returned by a

Controller

25. ASP.NET 3.5 Installed

Visual Studio 2008

Microsoft ASP.NET MVC Installed

 Download the current Beta

26. ASP.NET 3.5 Installed

Visual Studio 2008

Microsoft ASP.NET MVC Installed

 Download the current Beta

27. More Involved Examples

 Add/Edit/Delete and use of Server Controls
▪ Email me if you would like information on this
Custom HTML Helpers

 You can create your own Helper Classes and Extension
Methods which return formatted HTML strings
Unity Dependency Injection / IoC Container

 Framework for Dependency Injection and Controller
Factories
 Stand alone version and bundled with Enterprise Library
4.0

28. Using Partials as Templates for formatting/rendering

 For example a template for how a Movie is rendered
 HTML.RenderPartial(string partialViewName, object
Model)
Action Filters

 Attributes that can be applied to a Controller Action or
entire Controller
▪ Authorization
▪ Action Result
▪ Exception
▪ Custom
 For example for Logging/Tracing

29. Upgrading existing code will take a long time, better

for Greenfields projects
For now, applications which require richer user

interfaces will require more work with MVC
 Third party UI library vendors have started developing and
releasing updated controls
Some SEO issues, may require URL rewrite engine,

but can be done
Not officially supported on pre Windows Server

2003/IIS 6, but can work

30. If you are developing a new system it is worth

evaluating the pros and cons, it is not a silver
bullet however
ASP.NET MVC is much more in line with what is

happening elsewhere in the industry, for
example Ruby on Rails
We feel that the Pros outweigh the Cons in

general and are implementing ASP.NET MVC in
our new Web Applications wherever possible

31. http://www.asp.net/mvc/

 Official Site
http://weblogs.asp.net/scottgu

 Scott Guthrie
http://www.hanselman.com/

 Scott Hanselman
http://quickstarts.asp.net/previews/mvc

 Videos, Examples, Blogs
http://martinfowler.com/articles/injection.html

 Repository/Dependency Injection Pattern
http://www.pnpguidance.net/Category/Unity.aspx

 Unity
http://patramadass.emediait.com

 This presentation, example code