Download Introducing ASP.NET MVC 4 and Entity Framework

Introducing
ASP.NET MVC 4 and Entity Framework
Intertech’s Oxygen Blast – November 26, 2013
Davin Mickelson, [email protected]
An Intertech Course
Intertech
About Me…
 Developed web applications since 1998 with:
 FrontPage and Visual InterDev, FPSEs, ASP, COM.
 Perl, ColdFusion <cftag>, ASP.NET: C#, VB.NET, F#.
 Intertech Consultant/Instructor since 2005.
 Intertech Courses:





Complete ASP.NET 4.5 (5 days).
Programming in HTML5 with JavaScript and CSS3 (5 days).
Developing ASP.NET MVC 4 Web Applications (5 days).
Programming in C# (5 days)
Developing Applications Using Entity Framework 4.1 (2 days).
 I teach .NET, SQL Server BI, TFS, jQuery, MVC, HTML5, etc.
 Intertech blog: http://www.intertech.com/blog
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 2
New fishing hat
doesn’t work!
Intertech
ASP.NET MVC 4 Agenda, 1 of 3
 Purpose/History of MVC 4
 Versions/Features of MVC/Visual Studio
 Download Instructions
 Controllers
 ViewBag/ViewData and TempData
 Models
 Model Validation
 Views
 ASPX Forms and Razor View Engines
 Routing
 New MVC 4 Features
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 3
Intertech
Entity Framework Agenda, 2 of 3





Purpose/History of EF
Versions/Features of EF/Visual Studio
Download Instructions
MVC and EF Together
Three EF Methodologies
 Database First
 Model First
 Code First
 Querying EF
 LINQ to Entities
 Entity SQL
 EntityClient API
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 4
Intertech
MVC & EF Futures, 3 of 3





ASP.NET MVC 5
EF 6
Visual Studio 2013
.NET 4.5.1
Windows 8.1
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 5
Intertech
Three ASP.NET Web App Architectures
 ASP.NET Forms
 Been around since .NET 1.0 was released
 Visual Studio 2002+
 ASP.NET Web Pages
 Single Razor Web files - no code-behind files
 Visual Studio 2008+ Web Site or WebMatrix (free!)
 ASP.NET MVC
 Visual Studio 2008+ to develop these apps
 Today, we will look this architecture!
 <DEMO>
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 6
Intertech
What is MVC?
 Model – View – Controller (MVC)
 Originally developed in 1978 with Smalltalk at Xerox PARC
 In recent years, MVC has been used as a Web framework
 MVC is used with Java and Ruby
 Jakarta Struts, Ruby on Rails, JSF, Spring, and more
 “Separation of Concerns”
 The model, the view, and the controller are broken into
separate domains
 These domains may or may not be defined in separate
methods, classes, or assemblies
 There is no hard set of rules but rather conventions
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 7
Intertech
Introducing ASP.NET MVC
 Popular new way to develop ASP.NET Web applications.
 MVC applied to the ASP.NET framework.
 Already been done before with ALT.NET! Example:
Castle MonoRail http://www.castleproject.org/projects/monorail/
 Minneapolis ALT.NET UG: http://mplsalt.net/MainPage.ashx
 Microsoft’s release ASP.NET MVC has more pull, though.
 Based on file and folder naming conventions.
 High quality coding promoted by unit testing.
 Test Driven Development (TDD) is supported.
 Support for DI / IoC frameworks.
 Ninject, StructureMap, MEF, Castle Windsor, Spring.NET,
Autofac, Unity, etc.
 Simplifies testing parts of an app by using mock objects.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 8
Intertech
Why Use ASP.NET MVC?
 Hate the resource wastefulness of standard ASP.NET forms.
 Need unit testing.
 Prefer greater control over the HTML, CSS, and JavaScript sent to
the Web browser.
 Want refined URL addresses for better Search Engine Optimization
(SEO).
 Have previous experience with the MVC model in another language.
 Tired of standard Web forms and want to try something new and
cool!
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 9
Intertech
Why NOT Use ASP.NET MVC?
 Already supporting a large ASP.NET Web forms project that doesn’t
need this architecture.
 Prefer using the ASP.NET server controls.
 Prefer ASP.NET Rapid Application Development (RAD) environment
(drag and drop).
 Not a professional web developer. Prefer the simplicity of Web pages
in WebMatrix.
 Prefer controls having automatic state management (ViewState).
 Don’t need this level of control over the final HTML, CSS, and JS.
 Haven’t had time to sharpen your C#/VB programming skills with:
 HTML/CSS/JS, Lambda operator, LINQ, Extension methods,
Entity Framework, etc.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 10
Intertech
ASP.NET MVC vs. ASP.NET Forms
ASP.NET Web Forms
ASP.NET MVC
We know this stuff already!
Entirely new model we must learn
Supports ASP.NET Server Controls
Primarily supports raw HTML/JS
Automatic state management of controls
Manual state management
Drag and drop controls
“Scaffolded” (wizard) views and manual
Web page coding
Been around since 2002
1.0 released on April 9th, 2009
Weak or custom unit testing required
Encourages and includes unit testing
support!
Web Sites and Web Application Project (WAP)
WAP only!
Both ASP.NET frameworks are supported in VS 2008/2010/2012/2013+
Both have access to the five intrinsic objects (Session, Application, etc.)
Both support the use of the ASP.NET Provider models
(Membership, Profile, Sitemap, and more)
Both support EF and the popular JavaScript libraries: Modernizr, jQuery, etc.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 11
Intertech
ASP.NET MVC - Five Versions
Visual Studio
ASP.NET MVC
Visual Studio 2008
v1/v2 (both added to Visual Studio)
Visual Studio 2010
v2/v3/v4 (v2 native), v3 and v4 added
Visual Studio 2012
v3/v4/v5 (3.0 native), v4 and v5 added
Studio 2013
v4/v5
(both native)
Visual
ASP.NET
MVC is
a revolutionary
step for Microsoft
 This is the first time Microsoft has ever embraced the open
source model at this level
 The complete ASP.NET MVC source code can be downloaded
from CodePlex, modified, and then recompiled for your needs!
 http://aspnetwebstack.codeplex.com/
 Many free JavaScript libraries included such as jQuery,
Modernizr, and Knockout
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 12
Intertech
Create an ASP.NET MVC Project
 Pick a language (C# or VB) for your WAP
 Click File | New | Project | ASP.NET MVC 4 Web Application
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 13
Intertech
Create an ASP.NET MVC Project
 Choose a template, decide on a view engine, and select
whether to create a unit test project
 Visual Studio supports alternative (installed) testing frameworks:
NUnit, MBUnit, and more
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 14
Intertech
Project Created!
 There is a huge number of referenced
assemblies!
 Talk about embracing the open source community!
 Some are referenced .NET Framework
assemblies – System.<anything>
 Many are NuGet packages installed with the
selected project template
 They are installed in the \packages\ subfolder
 They are also copied to the WAP’s \bin\ folder
 Curious what they do?
 ILDasm.exe! <DEMO>
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 15
Intertech
Models, Views, and Controllers
 These three folders suggest where to define
the three domains
 Conventions:
 Each controller class must be in the Controllers folder
 Each controller class contain one or more action
methods
 Each view file is placed in subfolder named after a
controller class.
 Each view file maps to an action method of a
controller class
 Model classes can be created anywhere - the
Models folder is fine or in a separate .dll.
 The Shared folder contains shared resources such as:
Web pages, layouts, error view, and partial views.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 16
Intertech
Controllers - Purpose
 A Controller is responsible for handling incoming
requests and sending back the proper response.
 It is the first of the three MVC members to interact with the
request.
 A Controller class contains “action methods” that usually map to
views with the same name.
 Most typically, they interact with a Model to generate or
retrieve data and/or use business rules.
 They take the retrieved data and pass it off to a View for
generating a Web response to the user.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 17
Intertech
Controllers - Defining
 A Controller must implement IController interface and
must end in the name Controller.
 Usually, it will inherit from the Controller base class.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 18
Intertech
Controllers - Defining
 Alternatively, the class can implement the IController
interface
 This is a really simple controller that just returns a simple
message.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 19
Intertech
Controllers - Actions
 The simplest controller just returns HTML to the Web
browser
 IMPORTANT: By default, all public methods in a
controller class can be called from the Web browser
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 20
Intertech
Controllers - ActionResult
 Most controller methods return a type of ActionResult
ActionResult
Types
Purpose
Examples of Use
ViewResult
Displays a View
return View();
PartialViewResult
Displays a Partial View
return PartialView();
RedirectToRouteResult
Redirects to a route
return RedirectToRoute(“NamedRoute”);
RedirectResult
Simple URL redirection
return Redirect(“http://bing.com”);
ContentResult
Returns raw text to the browser
return Content(rssString,
“application/rss+xml”);
FileResult
Returns binary data to browser
return File(@”.\Doc1.docx”,
“application/vnd.ms-word”);
JsonResult
Returns an object serialized as Json
return Json(Car);
JavaScriptResult
Returns JavaScript intended to run
on the browser. Used with Ajax.
return JavaScript(“$(#elementName).hide();”);
HttpUnauthorizedResult
Returns code 401 – not authorized
return new HttpUnauthorizedResult();
EmptyResult
Doesn’t return. Ends.
Return new EmptyResult();
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 21
Intertech
Controllers – Passing Data
 Data is passed to a View using the ViewData or the
TempData dictionary collections.
 They store data as System.Object.
 ViewData is a ViewDataDictionary object
 Used for a single Request/Response.
 ViewBag, introduced with MVC 3, is usually preferred and
uses ViewData object.
 Stores data as “dynamic”,not Object - no casting required in View!
 TempData is a TempDataDictionary object.
 Used to preserve data between a RedirectResult or
RedirectToRouteResult.
 Stores data for the current and next HTTP Request/Response.
 Uses Session object behind the scenes.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 22
Intertech
Controllers – Passing Data
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 23
Intertech
Controllers – Passing Data
 The View and the final response displayed in IE 10.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 24
Intertech
Controllers - Adding
 New Controllers can be easily added to the project.
 There are many (hidden?) context menus available for launching
powerful MVC wizards.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 25
Intertech
Controllers - Adding
 Incredible scaffolding support is included!
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 26
Intertech
Controllers - Ajax
 Ajax calls can also be made of the controller.
 These are also public methods exposed from the controller class.
 The example below uses the ASPX Forms view engine.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 27
Intertech
Models – Purpose
 Business Logic (BL), Data Access Logic (DAL) – it’s all
defined here!
 Where you actually write the code is up to you.
 With the Model, you have the most flexibility as to where you’d
like to place the code
 The Model code can be located:




Right inside the Controller class (not recommended)
In classes defined in the Models folder
In classes defined elsewhere in the WAP
In a Class Library assembly for greater reuse
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 28
Intertech
Models - Purpose
 A Model is code that enforces business logic.
 It can also store and return data in a fashion that can ultimately
be bound to and displayed by a View
 There are many different types of models!
 Specifically, a model can be used for:
 Retrieving/Storing Data in an .xml file
 Retrieving/Storing Data in a database
 Pure business logic
 A model represents the intelligence of the system
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 29
Intertech
Models - Types
 Models can be based on classic ADO.NET methods
defined in CRUD methods of a DAL
 Often times referred to as POCOs (Plain Old CLR Objects)
 Models can also be based on Object-Relational Mapper
(ORM) software.
 Examples include:
 LINQ to SQL (Dead technology - avoid!)
 Entity Framework (More coming up!)
 NHibernate (a .NET version of Java’s Hibernate)
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 30
Intertech
Views - Description
 Two different View Engines
 ASPX Forms View Engine
 Razor View Engine (MVC 3+)
 They are never directly requested by the Web browser
 They are often used with .master pages/_layouts
 ASPX Views make use code nugget <%: %> syntax
 This is the same as typing out Response.Write() but shorter
 Razor uses a simplified code nugget @ syntax based on
Web Pages
 Transitioning from ASP.NET Forms to ASP.NET MVC?
 Consider initially learning MVC with ASPX View Engine
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 31
Intertech
Views - Adding
 Views give us full control to the HTML and JavaScript
mark up
 Views can be easily added to the project in the Solution Explorer
 IMPORTANT: Make sure you are adding it to subfolder!
 Best way to add view?
Right-click the code in an action method and click Add New…
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 32
Intertech
Views – HTML Helper Methods
 Views also make use of the HTML Helper methods
 For example:
@Html.TextBox("txtName", ViewData["Name"])
HTML Helper
Example Use
CheckBox
Html.CheckBox(“chkChoose”, true)
Radio Button
Html.RadioButton(“rbRadio”, “val”, false)
Hidden Form Field
Html.Hidden(“hField”, “CustomerID”)
Password Textbox
Html.Password(“pPassword”, “val”)
Text Area
Html.TextArea(“taTextArea”, “val”, 4, 10, null)
TextBox
Html.TextBox(“txtName”, “Davin”)
Drop-Down List
Html.DropDownList(“ddlColors”, new SelectList(
new [] {“Red”, “Green”, “Blue”}), “Pick One”))
ListBox
Html.ListBox(“lbColors”, new MultiSelectList(
new [] {“Red”, “Green”, “Blue”}))
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 33
Intertech
Views – HTML Helper Methods
 Different Types of Helper methods






Classic un-typed Helper methods (v1/v2 – no editor help)
Strongly-typed Helper methods (IntelliSense!)
Template Helper methods (Attempts full object code gen)
Rich Helper methods (Chart, WebGrid)
Your custom Helpers via Extension Methods <DEMO>
Many 3rd Party Helper methods (Fill in the gaps!)
 Telerik, ComponentSource, CodePlex, GitHub, etc.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 34
Intertech
System.Web.Routing.dll
 Installed with VS 2008 SP1 (.NET 3.5 SP1) and newer
 Used by Dynamic Data Web applications for routing web
requests
 Also used with ASP.NET MVC for routing requests to the
proper controllers
 Routing is configured in the /App_Start/RouteConfig.cs
file via a call from Global.asax.
 A static method called RegisterRoutes() registers URL
requests to controller action methods.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 35
Intertech
RouteConfig.cs – Default Route
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 36
Intertech
Default Route
 “Default” is the optional name of the route
 {controller} is the name of the controller class
 {action} is the name of the public action method in the
controller class
 {id} is an optional value passed to the action method as a
parameter
 If any or all are not specified, the default URL values are
used (http://server:<port #>/Home/Index)
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 37
Intertech
Routes can be confusing!
 More routes can be added
 They should be added from most specific to most generic
 The first route that matches a request wins
 Not necessarily the best match!
 Important points:
 The static RegisterRoute() method can be unit tested
 Routing is a silent but powerful fourth player in ASP.NET MVC
 You can also define “catchall” wildcard routes for handling all
kinds of data tacked onto the end of the query string
 Consider developing or downloading a route debugger
 There are free ones available
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 38
Intertech
Sample Routes (Ignore port 6831)





http://localhost:6831/
http://localhost:6831/product
http://localhost:6831/6
http://localhost:6831/product/junk
http://localhost:6831/product/Index
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 39
Intertech
Route Debuggers
 Check out some of the route
visualizers/debuggers
available.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 40
Intertech
Unit Testing ASP.NET MVC
 Good Unit Testing frameworks test all behavior, no
matter the visibility declarations
 They can test private, protected, internal, protected internal, and
public members
 Many unit testing frameworks exist including Visual Studio Testing
Framework, NUnit, xUnit.net, and more.

http://en.wikipedia.org/wiki/List_of_unit_testing_frameworks#.NET_programming_languages
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 41
Intertech
Unit Testing ASP.NET MVC
 Testing the RegisterRoutes() will ensure that no one has
changed them
 Testing the controllers can simulate user requests
 Web users will try to pass you anything; be ready for that!
 Testing the Models guarantee correct results
 Especially important if the models are in separate Class Library
assembly for reuse across projects!
 Testing ORM classes probably unnecessary (opinion!)
 Testing Views? Maybe
 Unfortunately, if you change the HTML/JS out just slightly, your
View tests will fail
 Some developer prefer not to tests their Views, or only certain
Views
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 42
Intertech
Test-Driven Development (TDD)
 Visual Studio Class Designer supports TDD by making all
new methods fail unit tests until they’ve been
implemented
 TDD is optional
 True TDD developers completely write the tests and then
write the code in the methods/properties to pass those
tests
 It is a form of Extreme Programming (XP)
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 43
Intertech
New ASP.NET MVC 4 Features
 New project template wizard.
 Better scaffolding of action methods and views.
 Improved “scaffolded” views that support mobile devices
via CSS media queries.
 Support for Web API project template supporting RESTful
services with OData queries.
 Support for OpenID and OAuth authentication including
3rd party sites such as Facebook and Yahoo.
 Single Page App project template.
 Mobile project template that include jQuery Mobile.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 44
Intertech
Introducing Entity Framework (EF)
 The ADO.NET Entity Framework (or simply EF) was
introduced with Visual Studio 2008 Service Pack 1.
 .NET 4.0 / Visual Studio 2010 support new EF designers, and a
better programming experience.
 EF 1 left a lot of “opportunities for improvement”. 
 So much so that the next version was EF 4 with .NET 4.0.
 The version EF 5 switched to Open Source!
 You can download it as NuGet package.
 EF 6 was released with VS 2013.
 Learn more here:
http://msdn.microsoft.com/en-us/data/aa937723
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 45
Intertech
Introducing Entity Framework (EF)
 EF is a programming model which attempts to lessen the
gap between database constructs and object oriented
programming constructs.
 Using EF, you can interact with a relational database without ever
seeing a line of SQL code (if you so choose).
 Rather, when you apply LINQ queries to your strongly typed
classes, the EF runtime will generate proper SQL statements on
your behalf.
 By way of another example, rather than updating database data
by finding a row, updating the row, and sending the row back for
processing using a batch of SQL queries, you can simply change
properties on an object and save its state.
 The EF runtime will update the database automatically.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 46
Intertech
Introducing Entity Framework (EF)
 As far as Microsoft is concerned, the ADO.NET Entity
Framework is a new member of the data access family not meant to replace the connected or disconnected
layers.
 However, EF works really nicely with MVC.
 It saves you an incredible amount of typing over the more
primitive world of SQL queries and row/column collections.
 .NET 4.0+ ships with EF providers for Microsoft SQL
Server databases.
 Many third party databases (Oracle, MySQL, etc.) provide EFaware data providers.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 47
Intertech
Introducing Entity Framework (EF)
 The strongly typed classes used within EF are termed
entities.
 Entities are a conceptual model of a physical database which
maps to your business domain.
 Formally speaking, this model is termed Entity Data Model
(EDM).
 While the EDM is a client side set of classes which map to a
physical database, understand that the entities need not map
directly to the database schema in so far as naming conventions
go.
 Your entity classes can be restructured to fit your needs, and the
EF runtime will map your unique names to the correct database
schema.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 48
Intertech
EF Example
 For example, assume you have the following physical
database table in a SQL Server database:
 If you were to generate an EDM for the Inventory table of
the AutoLot database, the entity will be called (by default)
Inventory.
 However, you could rename this class to Car and rename the properties which
map to the columns of the Inventory table.
 Because of this loose coupling, the entities can be shaped to closely model your
business domain.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 49
Intertech
EF Example
 If you were to generate an EDM for the Inventory table of
the AutoLot database, the entity will be called (by default)
Inventory.
 However, you could rename this class to Car and rename the
properties which map to the columns of the Inventory table.
 Because of this loose coupling, the entities can be shaped to
closely model your business domain.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 50
Intertech
EF Example
 Consider the following Program class, which will add a
new row to the Inventory table of AutoLot, using the Car
entity class, and a related class named AutoLotEntities.
 This class is called an object context, whose job it is to
communicate with the physical database on your behalf.
class Program
{
static void Main(string[] args)
{
// Connection string automatically read from generated config file.
using (AutoLotEntities context = new AutoLotEntities())
{
// Add a new record to Inventory table, using our entity.
context.Cars.AddObject(new Car() {
AutoIDNumber = 987, CarColor = "Black",
MakeOfCar = "Pinto", NicknameOfCar = "Pete" });
context.SaveChanges(); // Save changes back to database!
}
}
} © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 51
Copyright
Intertech
ObjectContext Members
Member of ObjectContext
Meaning in Life
AcceptAllChanges()
Accepts all changes made to entity objects within the object context.
AddObject()
Adds an object to the object context.
DeleteObject()
Marks an object for deletion. Must still SaveChanges().
ExecuteFunction()
Executes a stored procedure in the database.
ExecuteStoreCommand()
Allows you to directly send a SQL command to the data store.
GetObjectByKey()
Locates an object within the object context by its key.
SaveChanges()
Saves all updates to the data store.
CommandTimeout
This property gets or sets the timeout value, in seconds, for all object context
operations.
Connection
This property returns the connection string used by the current object context.
SavingChanges
This event fires when the object context is saving changes to the data store.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 52
Intertech
Three Ways to Use EF
 Database First
 A model and ObjectContext class is automatically built based on
an existing database.
 Model First
 A model is built first, then EF automatically creates the database
and the ObjectContext class
 Code First
 Classes are created by the developer that inherit from
DBContext.
 EF creates the underlying database, typically a LocalDB instance
of SQL Express.
 No .edmx model is created – the classes are the model!
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 53
Intertech
Three Layers (Database/Model First)
 All three layers of the Entity Data Model (EDM) are
defined in the *.edmx file.
 Conceptual Layer
 This represents the entities and their relationships in the model
 Physical Layer
 This represents the underlying tables in the database
 Mappings
 This represents the mapping from model to database.
 Most settings (not all!) can be made using the designer.
 Each new version of EF released adds more functionality to the
designer.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 54
Intertech
Database First
 Most EF applications original started out this way before
EF 4.1
 May be the most likely way you use EF
 Oldest way of using EF
 Greatest support in Visual Studio
 Model validation more difficult
 Must use “Buddy classes” so
data annotations/validation rules
are not lost.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 55
Intertech
Model First
 A very flexible pattern
 Allows you to design the model using prototypes in the
Toolbox.
 Will use LocalDB database until you change connection
string in Web.config
 Still using Buddy classes
for model validation
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 56
Intertech
Code First
 Most flexible to create and easiest for programmers.
 No visible .edmx designer file created
 Database created in /App_Data/ using EF base classes
 DBContext represents the model
 DBSet represents an entity
 Database can be recreated:
 Every time the web app is started
 When the model changes
 Data is “seeded” (populated) during application startup in
Global.asax
 Override Seed() method
<MVCMusicStore Demo>
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 57
Intertech
Querying Entity Framework – 3 ways
 LINQ to Entities
 Most commonly, you will use LINQ Query Expressions to retrieve
data from EF.
 Check out the free LINQ editor, LINQPad.
 Entity SQL
 Similar to the standard SQL language, this alternate SQL language
can be used to query EF.
 SELECT VALUE c FROM AWLTEntities.Customers AS c WHERE
c.FirstName = ‘Jim’
 EntityClient API
 Programming can also be done directly against the EntityClient API.
 Similar to classic ADO.NET but objects are Entity versions.
 EntityConnection, EntityCommand, EntityDataReader, etc.
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 58
Intertech
Microsoft Tool Futures
 ASP.NET MVC 5
 Is included with VS 2013 next month, Available for VS 2012 now!
 Includes ASP.NET Identity,Twitter Bootstrap in the MVC
template, Authentication Filters, Filter overrides, more…
 EF 6
 Asynchronous data access, Better Code-First Support, more…
 Included with VS 2013
 Visual Studio 2013, looks a little different but easier to
use than VS 2012
 RTM’d in August, 2013
 Support added for Windows 8.1, EF6, and MVC 5
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 59
Intertech
Microsoft Tool Futures
 .NET 4.5.1
 Not that many new features – .NET 4.5 just came out!
 Suggested moving to NuGet package release
 Obvious support added for Windows 8.1 Store front apps
 Windows 8.1





New Start button offering shutdown option
Three apps simultaneously can run on Tile view
Store front apps are fun to build with C#, VB, or JavaScript.
All your JavaScript skills transfer over check it out!
NOTE: Must develop on Windows 8/8.1 (not Windows 7 or Server
2012)
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 60
Intertech
Thank you!
 Question?!?
 Davin Mickelson
 [email protected]
 Shoot me an email!
Copyright © Intertech, Inc. 2013 • www.Intertech.com • 800-866-9884 • Slide 61