Introduction to ASP.NET MVC by LearnNowOnline

Introduction to ASP.NET MVC

Learn More @ http://www.learnnowonline.com Copyright ÂŠ by Application Developers Training Company

Objectives • Understand the basics of the Model-ViewController pattern • Explore the differences between ASP.NET Web forms and MVC applications • Build a sample MVC application and explore its structure

Agenda • The Model-View-Controller Pattern • Differences Between MVC and Web Forms Applications • Building a Simple MVC Application with Visual Studio

The Model-View-Controller Pattern • ASP.NET MVC is a revolutionary way to develop Web applications    

Built on Model-View-Controller pattern Separation of concerns Invented in 1978 by Trygve Reenskaug Very popular in Web development frameworks

The MVC Architecture • Three primary components  Model  View  Controller

• User interaction with application 1.Interacts with Web page 2.Controller handles request 3.Notifies model of changes  Controller selects a view  Await new user interaction Learn More @ http://www.learnnowonline.com Copyright © by Application Developers Training Company

Anatomy of a Request HTTP Request HTML Response

View

Controller

Model

Optional Persistent Storage

Learn More @ http://www.learnnowonline.com Copyright ÂŠ by Application Developers Training Company

ASP.NET MVC • Microsoft’s newest Web development framework  Easy to implement design principles and patterns  Integral part of ASP.NET

• First implementation by Scott Guthrie • Built using core ASP.NET features

Differences Between MVC and Web Forms Applications • ASP.NET Web forms was revolutionary in its day    

Rich infrastructure for Web version of desktop applications Abstracts limitations of HTTP Uses ViewState as a major feature Drag and drop development interface

• Problems with Web forms    

Little control over HTML ViewState can bloat Limited support for testing Complicated page lifecycle

The Tenets of MVC • • • •

Separation of concerns Convention over configuration Keep it DRY: Don’t Repeat Yourself Be helpful, but get out of my way

Web Forms vs. MVC Extensibility • ASP.NET has a provider model • MVC has a more powerful pluggable model • Options  Use the default component  Extend the default component  Replace the default component

Web Forms vs. MVC Blending of Concerns

• Web forms almost forces combination of view and controller • False sense of separation from code behind files  Reality: close coupling

• MVC’s separation of concerns encourages good coding practices  Ideally suited to Web application development

Web Forms vs. MVC

MVC Serves Methods, Not Files • Huge difference • File request: http://www.example.com/index.aspx?ID=5 • Method request: http://www.example.com/Home/Details/5  Maps to Details action method  Of Home controller  Item ID of 5

Web Forms vs. MVC Testability

• Testing helps make applications more robust in the face of changes • Unit test automates verification of a method • Can use the test-driven development methodology • Web forms make automated testing almost impossible

Web Forms vs. MVC Control over HTML

• Web forms server controls provide rich functionality  Produce unreadable, monolithic blocks of HTML

• MVC gives you complete control over HTML

Web Forms vs. MVC Open Source

• MVC source code is available • Liberal open source license: Microsoft Public License

Building a Simple MVC Application with Visual Studio • Building MVC applications can be efficient, because:  Web forms often require fragmented code  MVC’s convention over configuration  MVC tools in Visual Studio 2008 and 2010

• Best of all worlds with MVC

MVC Project Templates • Includes one Visual Studio Project template  Available for VB and C#

• Includes templates for three project types  Internet Application template o

Basic but fully functional MVC application

 Intranet Application template o

Same as Internet template, but uses Windows authentication

 Empty template o

Sets up project structure but no controllers or models

Upgrading from MVC 2 to 3 • Can install MVC 3 side-by-side with MVC 1 and 2 • When ready, upgrade to MVC 3 • Process is manual  Change a GUID, copy files, change web.config, etc.  Better to just create a new project and move stuff?  Release notes cover the basic steps

• Microsoft’s Eilon Lipton has an unsupported migration tool

Learn More! • This is an excerpt from a larger course. Visit www.learnnowonline.com for the full details! • Learn more about MVC on SlideShare: • Working with Controllers and Actions in MVC