Brad Abrams : ASPMVC

Business Apps Example for Silverlight 3 RTM and .NET RIA Services July Update: Part 15: ASP.NET MVC

BradA — Thu, 30 Jul 2009 19:00:00 GMT

Continuing in our discussion of Silverlight 3 and the update to .NET RIA Services. I have been updating the example from my Mix09 talk “building business applications with Silverlight 3”. I customer recently asked about using ASP.NET MVC and Silverlight with RIA Services. There specific scenario was an application with the complex admin interface in Silverlight but using ASP.NET MVC for the consumer facing part of the web to get the maximum reach. The customer wanted to share as much of their application logic as possible.

So, to address this, i thought I’d update my Mix 09 demo to have an ASP.NET MVC view as well as a silverlight view.

You can watch the original video of the full session

You can see the full series here

The demo requires (all 100% free and always free):

VS2008 SP1 (Which includes Sql Express 2008)
Silverlight 3 RTM
.NET RIA Services July '09 Preview
ASP.NET MVC 1.0

Also, download the full demo files and check out the running application.

The architecture we are going to look at today us focused on building the ASP.NET MVC head on the RIA Servces based app logic. As you will see this is easy to do and shares all the great UI validation support.

To start with I took the original application and deleted the MyApp.Web project and added a new project that is ASP.NET MVC based. You could have just as easily added another web project to the same solution.

Then I associated the Silverlight application with this web project. Be sure to turn on the RIA Services link as well. This is what controls the codegen to the Silverlight client.

Then i copied over the Authentication related DomainServices from the web project.

Then i added my northwind.mdf file to App_Data, built my Entity Framework model and finally added my domain service and updated it exactly the way did in Part 2. The one tweak we need to do is make each of the methods in the DomainService virtual.. this has no real effect on the silverlight client, but it allows up to build a proxy for the MVC client.

[EnableClientAccess]

public class SuperEmployeeDomainService : LinqToEntitiesDomainService<NORTHWNDEntities>

    public virtual IQueryable<SuperEmployee> GetSuperEmployees()

        return this.Context.SuperEmployeeSet;

    public override void Submit(ChangeSet changeSet)

        base.Submit(changeSet);

    public virtual void UpdateSuperEmployee(SuperEmployee currentSuperEmployee)

        this.Context.AttachAsModified(currentSuperEmployee,

                                      ChangeSet.GetOriginal(currentSuperEmployee));

Running the MyAppTestPage.aspx should show that we have the same Silverlight app up and running..

We can now focus on the ASP.NET MVC part of this.

In the Controllers direction, open up HomeContollers.cs.

   1: [HandleError]

   2: public class HomeController : Controller

   3: {

   4:    SuperEmployeeDomainService domainService =

   5:        DomainServiceProxy.Create<SuperEmployeeDomainService>();

Line 5 calls a factory method that creates a DomainService wrapper.. this allows you to have a clean, direct calling syntax for the DomainService, but allows the system to run through it’s standard pipeline of validation, authorization, etc. Note, with the current CTP, you will need to reference DomainServiceExtensions.dll from this sample to get this functionality.

   1: public ActionResult Index()

   2:  {

   3:      return View("Index", domainService.GetSuperEmployees());

   4:  }

Then index is very easy.. we simply pass the results of calling GetSuperEmployee() as our model. This allows us to share any business logic that filters the results… I can write it once and share it between my Silverlight and ASP.NET MVC app.

Nothing at all remarkable about the view.. Index.aspx in the \Views directory.

   1: <%@ Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master"

   2:  Inherits="System.Web.Mvc.ViewPage<IQueryable<MyApp.Web.Models.SuperEmployee>>" %>

3:

   4: <asp:Content ID="indexTitle" ContentPlaceHolderID="TitleContent" runat="server">

   5:     Home Page

   6: </asp:Content>

7:

   8: <asp:Content ID="indexContent" ContentPlaceHolderID="MainContent" runat="server">

9:

  10: <h2>List of Employees</h2>

  11: <ul>

  12: <% foreach (var emp in Model) { %>

13:

  14: <li>

  15:     <%=Html.ActionLink(emp.Name, "Details", new { id = emp.EmployeeID })%>

  16:     Origin:

  17:     <%=Html.Encode(emp.Origin)%>

  18: </li>

  19: <% } %>

20:

  21: </ul>

22:

  23: </asp:Content>

In line two, we set up the Model type to be IQueryable<SuperEmployee>… notice this is exactly what my DomainService returned.

The in lines 15-18 I get strongly typed access to each SuperEmployee.

Here is how it looks:

Next, let’s look at the controller action for the Details view..

   1: public ActionResult Details(int id)

   2: {

   3:     var q = domainService.GetSuperEmployees();

   4:     var emp = q.Where(e=>e.EmployeeID==id).FirstOrDefault();

5:

   6:     return View(emp);

   7: }

Again, very simple, here we do a Linq query over the results of calling our business logic. The cool thing about the composition of Linq is that this where clause passes from here, to the DomainSerivce, to the Entity Framework model and all the way to the database where it is executed as efficient tsql.

The Details.aspx view is just as simple as the view above, basically just accessing the model.

Ok – so the read case is easy, what about update?

Let’s look at the Edit action in the controller..

   1: public ActionResult Edit(int id)

   2: {

   3:     var q = domainService.GetSuperEmployees();

   4:     var emp = q.Where(e => e.EmployeeID == id).FirstOrDefault();

5:

   6:     return View(emp);

   7: }

Again, very similar to the Details action we saw.. this simply populates the fields.

Now let’s take a look at edit.aspx view for this action. We need a simple data entry form..

First, we add a Validation summary at the top of the form. This is where we will display all the validation issues for the page.

   1: <%= Html.ValidationSummary("Edit was unsuccessful. Please correct the errors and try again.") %>

Next, we include some standard HTML for each field we need filled out:

   1: <p>

   2:     <label for="Name">Name:</label>

   3:     <%= Html.TextBox("Name", Model.Name) %>

   4:     <%= Html.ValidationMessage("Name", "*") %>

   5: /p>

   6: <p>

   7:     <label for="Name">Gender:</label>

   8:     <%= Html.TextBox("Gender", Model.Gender) %>

   9:     <%= Html.ValidationMessage("Gender", "*")%>

  10: </p>

Notice in line 4 and line 9 we are adding validation hooks…

If there are any fields in the type that we don’t want to display, we still need to include them here so they will be in the postback data…

<p>

<%= Html.Hidden("EmployeeID", Model.EmployeeID)%>

</p>

The other thing we want in postback data the set of unedited “original” data.. this is so that we can do concurrency checks with the database.

<%= Html.Hidden("orginal.EmployeeID", Model.EmployeeID)%>

<%= Html.Hidden("orginal.Gender", Model.Gender)%>

<%= Html.Hidden("orginal.Issues", Model.Issues)%>

<%= Html.Hidden("orginal.LastEdit", Model.LastEdit)%>

<%= Html.Hidden("orginal.Name", Model.Name)%>

<%= Html.Hidden("orginal.Origin", Model.Origin)%>

<%= Html.Hidden("orginal.Publishers", Model.Publishers)%>

<%= Html.Hidden("orginal.Sites", Model.Sites)%>

Notice here the naming convention of original.blahh.. as you will see later, this matches the name of the argument on the controller action. Let’s flip back to the controller action and take a look..

   1: [AcceptVerbs(HttpVerbs.Post)]

   2: public ActionResult Edit(SuperEmployee emp, SuperEmployee orginal)

   3: {

4:

   5:     if (ModelState.IsValid)

   6:     {

   7:         domainService.AssociateOriginal(emp, orginal);

   8:         domainService.UpdateSuperEmployee(emp);

   9:         return RedirectToAction("Details", new { id = emp.EmployeeID });

  10:     }

11:

  12:    return View(emp);

13:

  14: }

Notice my method takes two arguments, emp, which is the current employee as it has been updated from the form and the “original” employee that is mapped back from the hidden html fields.

Then in line 7, we associate the original value with the employee… this effectively makes it so that calls in the DomainService class to ChangeSet.GetOriginal() will return the right value. Next we call UpdateSuperEmployee() on the business logic. Here we do all the validation defined for the model including running custom validation code. If validation fails, the error information will be shown on the form. Otherwise the data is eventually saved to the database.

What I have show is building an ASP.NET MVC application that shares the exact same application logic as my Silverlight client. This includes things such as data validation that shows right through to the UI. To bring it home, here is an example of the exact same validation error first in the Silverlight client, then in the ASP.NET MVC client…

Mix Essentials Event in South Africa in June

BradA — Thu, 29 May 2008 17:12:41 GMT

I am very excited that Joe Stagner and I will be heading to South Africa the week of June 23rd. While we are there, we will have a chance to interact with the very passionate .NET community in both Johannesburg and Cape Town.

The South Africa Mix Essentials is an excellent chance to have a conversation about the next generation of web and designer technologies. I hope you can make it!

Same great content, two venues:

Johannesburg 24 June 2008 (Register)
Cape Town 26 June 2008 (Register)

I'll be giving some very cool web technology talks while I am there including:

- Silverlight 2 (beta2!) Developer overview where I will talk about our generalal goals for Silverlight in the RIA space and walk through how to build a Silverlight application end-to-end.

- Building Great Web Applications with ASP.NET AJAX where I will talk about some of the new AJAX\JavaScript advances in VS2008 and .NET Framework 3.5 SP1. This will be an all-demo-no-slides sort of talk, so it will be a ton of fun!

- ASP.NET Futures including ASP.NET Dynamic Data and ASP.NET MVC.

While I am there, I will also do a couple of user group events.. here is what we have locked so far:

On June 23rd, I will be talk to a local .NET users group in Johannesburg about Silverlight 2! Thanks to Craig Nicholson for getting this setup.

On June 25th, I will be talking to a local .NET Users group in Cape Town about ASP.NET MVC. Thanks to Hilton Giesenow for getting it setup.

I have never been to South Africa before, so any thoughts on what would be good to see while I am there? See you there!

update: added the Johannesburg event, thanks Craig!

Thank you North Carolina!

BradA — Sat, 12 Apr 2008 03:07:49 GMT

I had a great trip in North Carolina… In addition to a fun time with my extended family, I had a chance to take two days “off” vacation and visit with three Fortune 500 companies, give a Framework Design Guidelines training class to the Visual Studio North Carolina office and speak at the Triangle Area .NET User’s group.

Overall, I am very impressed with the .NET community in North Carolina. I found a ton of passion and interest in Silverlight 2 in both consumer facing Internet applications as well as browser clients for internal line of business applications. I was also impressed with the interest in ASP.NET Dynamic Data (which we just did an updated preview of) and there were a few folks that were super excited about ASP.NET MVC.

At the .NET User's group there were just over 90 people there and a I was lucky enough to have a local control vendor FarPoint, sponsored this event in a very North Carolina way. Their team barbequed a pig! Several members of the team took the day off to prepare the BBQ, slaw, baked beans and you guessed it – banana pudding! It was a great change from the normal pizza user group fair. Thanks FarPoint! (check out the pictures from Steve Jackle)

Enjoying the BBQ

I had a great time doing the demos for the user’s group meeting I covered three main areas via an all-demo-no-slides format where I coded up these apps from scratch. It was a lot of fun and the interaction with the audience was great!

Enjoying the conversation

Silverlight 2

I showed a couple of cool demos from http://silverlight.net then did an end-to-end coding demo. I created a new Silverlight project, showed how to write a basic Xaml layout, then did client side code behind in C#, customized the UI in blend including some cool animations, then I used the great visual layout capabilities of Expression to build standard form based UI complete with a DataGrid. I then went back to the server project and created a data access layer with Linq, encapsulated it with a WCF service and consumed that from the Silverlight client!

Download the completed Silverlight 2 WFC demo in C#

Download the completed Silverlight 2 WFC demo in Visual Basic

ASP.NET MVC

I showed how to build (and test!) a basic ASP.NET MVC application based on a LINQ datamodel. I created a solution with a web application and unit test project. I added a data access layer with Linq, created some a new controller action with business logic then created a very clean view to display the data. I then showed how to test one of the action methods with a test specific subclass.

Download the ASP.NET MVC completed demo in C#

Download the ASP.NET MVC completed demo in VB

ASP.NET Dynamic Data

I demoed the latest bits by creating a linq data model with a ton of tables. I then enabled the Dynamic Data to auto generate UIs… the result (with no code) was a complete application to create, edit, update and view all of the data. I then showed three different layers to customize this UI. I created a Products class and added custom metadata to display how the products table is displayed including an allowed range and a tooltip. Then I customized how all the ListDetails pages are displayed using the ListDetails.aspx template and finally I changed how all strings in the application are displayed by changing the Item template.

Download the ASP.NET Dynamic Data completed demo in C#

Download the ASP.NET Dynamic Data completed demo in VB

ASP.NET MVC in CodePlex and Extensible Unit Testing

BradA — Tue, 11 Mar 2008 05:35:00 GMT

Phil has some good thoughts on ASP.NET MVC preview 2 and beyond.

A couple of key things that I think are very cool with this project.

CodePlex builds -- The team is very excited to be able to ship out the source code and unit tests for ASP.NET MVC through it's release cycle on CodePlex. We will still do regular CTPs and Betas and RTMs, outside of CodePlex in the normal way. But CodePlex allows more frequent releases if you want to watch the evolution of the product more closely.

Unit test integration -- We are very exited to be working closely with the TDD community on the ASP.NET MVC framework. In fact the MbUnit folks have already released updated installers that integrates support for MbUnit into ASP.NET MVC.. I am sure the others will add support shortly. Joe Cartano of the Web Tools team posted an updated streamlined walkthrough on how to do so using NUnit and Rhino Mocks as an example.

ASP.NET MVC Preview 2

BradA — Wed, 05 Mar 2008 20:21:00 GMT

A few weeks ago, ScottGu blogged about the ASP.NET MVC Framework roadmap... I am happy to announce that we have taken the next step on that roadmap with the availability of the ASP.NET MVC Framework update.

ASP.NET MVC Preview 2

The ASP.NET MVC Preview 2 release contains the latest version of the ASP.NET MVC framework and related Visual Studio tools support.

In this release we have incorporated a ton of feedback, added some new features and enhanced the tooling support!

Check it out at http://asp.net/mvc

Find some great video overviews of the new features.

Walk through the MVC Quickstarts and use the MVC forums to ask questions and get help!

ASP.NET MVC Example Application over Northwind with the Entity Framework

BradA — Tue, 29 Jan 2008 21:14:00 GMT

Over last month over the holidays, Lance Olson and I spent some time porting ScottGu's excellent MVC example over the Entity Framework. I thought I'd share the results here and get your thoughts\feedback.

12-11-08: I updated a few links and the example to match latest bits.

For this example, you will need:

VS2008 (Free trial )
ASP.NET 3.5 Extensions (Update: use lastest bits from http://asp.net/mvc )
ADO.NET Entity Framework Tools Dec 07 Preview (Update: No longer needed, in VS2008 SP 1)
Northwind sample database (just northwnd.mdf)

If you are the type that likes to eat your desert first, you can skip to the end and just download the full working solution (Update: download this version of the sample that works with latest bits).

Getting Started

File/New Project - Select ASP.NET MVC Web Application and Test

This creates a single solution with both a web application project as well as a project we can use for unit testing. Both are pre-populated with the basic stuff you need to get going.

Creating the Routes

One of the powerful new features that ASP.NET MVC brings to the table is the ability to customize the URLs that access your application. The URL routing feature explicitly breaks the connection between physical files on disk and the URL that is used to access a given bit of functionality. This is important for Search Engine Optimization as well as general usability of the website. For example, rather than access http://localhost/Products/ItemDetails.aspx?item=42 you can now very give a pretty URL such as http://localhost/Products/CodFishOil

This is done by creating a route table in the global.asax file in the MVC Application. Luckily for us, the defaults included in the template work perfectly this application.

RouteTable.Routes.Add(new Route
{
    Url = "[controller]/[action]/[id]",
    Defaults = new { action = "Index", id = (string)null },
    RouteHandler = typeof(MvcRouteHandler)
});

This code spells out the format of the URLs we want to use for our site. In particular, a URL of the format

http://localhost/Products/Details/CodFishOil

would translate to the ProductsController class (notice we add the "Controller" suffix to the class name to make these classes stand out in the object model at design time). Then the Action is a method on that class called Details and finally the argument to that details method is CodFishOil.

It is of course possible to have other formats, simply by changing he regular expression in the URL pattern string.

Creating the Model

The model represents the data you are going to use in the application. In our case, this is a pretty good place to start the core of the application.

In the App_Data direction of the MVCApplication copy the Northwind.mdf file. Northwind is likely the most common example database we have for SqlServer... You can download it from the official location, or for just the raw file, feel free to grab it from here.

Next, we need to create a LINQ model on top of northwind to make it easier to work with... You can do this with NHibernate, LinqToSql, Entity Framework , or any other .NET OR-Mapping technology. As long as it results in .NET Object, the ASP.NET MVC framework can work with it. In this case I am going to use the Entity Framework.

Right click on the Models directory and select add new item

In the dialog select ADO.NET Entity Data Model.

In the wizard, select "Generate from Database" and then go with the default "Northwnd" connection string.

For our demo, we are only going to use the Categories, Products and Suppliers tables, but you could of course extend this demo to include a richer feature set. But for now, unselect the Views and Stored Procedures and all the tables except those three..

When you click finished, VS will create a set of .NET classes that are custom built for accessing this database and we get a nice designer for visualizing the data relationships.

Notice, that the default names given to these classes still use the plural names from the database, but in our OR-Mapping they represent single instances, so to make the code easier to read, go in and change all the table names to their appropriate singular form: Category, Product and Supplier. Then Navigation properties on Product needs to be singular as there is only one Category and Suppler for each product.

Next we need to cleanup the namespace so things look pretty in our code... Right click on the design surface then set the properties such that namespace is "NorthwindModels" and the Entity Container name to "NorthWindEntities"

While we are not 100% done with the model, we have gotten the lion's share of it complete.. Let's switch over and look at the controller.

Creating the Controller

Right click on the Controller directory and select "Add new Item". In the dialog find MVC Controller and be sure to give it a name that ends in the Controller suffix. In our case we are writing the ProductsController.

OK, we are ready to start working in ProductsController.cs

The goal of the controller is to prepare the model for the view. We want to bring as much logical as possible out of the view because it is so hard to test in the view. So in the controller, we are going to be accessing the Model and getting it all set up so all the view has to do is spit out some data.

The first thing we need, is access to our database.

1. Add the right namespaces... Linq and a reference to our OR mapping.

using System.Linq;
using NorthwindModel;

2. Next, we create an instance of the NorthwindEntities container class. Nearly all of our actions will access this class.

    public class ProductsController : Controller
    {
        NorthwindEntities Northwind = new NorthwindEntities();

OK, now we are ready to create our first action.. Listing all the categories. Remember the job of the controller is to prepare the model for the view.. When defining a new action, I like to start off by putting a comment that reminds me what the URL is that access this functionality.

The next thing we do is access the Categories table from the model. I snap the results to a generic collection class (you may have to add a reference to System.Collections.Generic) then we pass the results to the view named "Categories". This is a very simple example, later we will see more complex logic here.

//URL: http://localhost/Products/Categories
[ControllerAction]
public void Categories()
{
List<Category> categories = Northwind.Categories.ToList();
RenderView("Categories", categories);
}

Next step, we need to create the "Categories" view..

Creating the View

Right click on the Views folder, add new Directory "Products". This so we can organize all our views cleanly. The Right click on Views/Products folder and add new item MVC View Content Page. We are going to leverage the Master Page that comes with the default project to make this look a little more pretty.

Call it Categories.aspx... It is important that the view name matches the first argument to the RenderView method above.

The default project puts the master page in Views/Shared/Site.Master

In order to get the strongly typed access to the ViewData we are passing in from the controller, we need to tell the View Page, the type to expect. This is done by opening up the codebehind (Categories.aspx.cs) and changing the derived type from:

    public partial class Categories : ViewPage
    {
    }
to:

public partial class Categories : ViewPage< List<Category> > 
{
}

Then you simply write clean, simple, designable HTML. Notice here I am looping over all the items returned in ViewData and pushing them out as a link. I use the MVC helper method Html.ActionLink to create the URL for the List action with the appropriate product ID.

    <h2>Browse Products</h2>

    <ul class="categorylisting">
    
      <% foreach (var category in ViewData) { %>
    
        <li>
            <%= Html.ActionLink(category.CategoryName, new { action="List", id=category.CategoryName }) %>            
        </li>
    
      <% } %>
        
    </ul>

OK, we are finally ready to run it!

Hit F5, and navigate to the controller action we just wrote on http://localhost:64701/products/Categories

Clicking on any of the links give you an error, because we haven't written the List action yet.. we will do that next.

As an aside, if like me, you are in the habit of using "View in Browser" on aspx pages you develop, you are likely to see this error. To reproduce, right click on Categories.aspx and select View in browser.

You get an error. Why? Well, remember with the MVC model, all execution goes through the controller, the views themselves are not runnable. Future tooling will make this better, but in the mean time, use F5 or you can "run in browser" with default.aspx.. just be sure you have built the solution first!

The List Action, View

OK, let's now go back and add the List action that we are missing. What we need to do here is find all the products with a give Category. First I need to get all the products out of the model, then I need to ensure that the Category references are loaded. The entity framework offers an explicit loading model by default. As such you have to explicitly load any tables you need. And finally we render the view.

//example URL:http://localhost:64701/products/List/Confections
[ControllerAction]
public void List(string id)
{
    List<Product> products = Northwind.GetProductsByCategory(id);

    //prepare the view by explicitly loading the categories  
    products.FindAll(p => p.Category == null).ForEach(p => p.CategoryReference.Load());

    RenderView("ListingByCategory", products);

}

Notice, i am calling a custom method on the NorthwindDataContext class... Personally I like the idea of keeping all the data access logic encapsulated in that class. So to define this method, Right click on the Model, add new Item, select CodeFile and name it NorthwindDataContext.cs and give it the implementation.

using System;
using System.Collections.Generic;
using System.Linq;

namespace NorthwindModel
{
    public partial class NorthwindEntities
    {

    }
}

Now you can easily add data access methods to this class... such as the GetProductsByCategory() method we use above.

public List<Product> GetProductsByCategory(string category)
{
    return Products.Where(p => p.Category.CategoryName == category).ToList();
}

Next, we need to add the ListingByCategory view... We follow the same steps from above to add a ListingByCategory.aspx page in the Views/Products/ directory.

This time, we should make the ViewData be of type List<Products>

public partial class ListingByCategory : ViewPage< List<Product> > 
 {
 }

Next, to implement the view, we simply loop over the view data and spit it out in the right format.

  
<%--Print out the catagory name--%>  
  <% foreach (var product in ViewData) { %>
  <% if (product.Category.CategoryName != null) {  %> 
    <h2>  <%=product.Category.CategoryName  %></h2> 
    <% break; %>
 <%} //end if %>
 <%}//end foreach %>
        
    <ul class="productlist">
    
        <% foreach (var product in ViewData) { %>
        
            <li>
                <img src="/Content/Images/<%=product.ProductID%>.jpg" alt="<%=product.ProductName %>" /> 
                <br/> 
                <a href="/Products/Detail/<%=product.ProductID %>"> <%=product.ProductName %> </a>
                <br />
                Price: <%=String.Format("{0:C2}", product.UnitPrice)%> 
                  <span class="editlink"">
                    (<%= Html.ActionLink("Edit", new { Action="Edit", ID=product.ProductID })%>)
                </span>
           
            </li>
    
        <% } %>
        
    </ul>

Once you add the /Content/Images directory from the sample project you get this:

Unit Testing

One of the primary reasons for using the MVC model is to enable Test Driven Development and more generically Unit Testing. Unit testing UIs is notoriously difficult. Automation is fragile and hiring an army of testers to click on buttons is not always cost effective. The model MVC is going for is to separate out as much code (and therefore potential bugs) as possible into the Model and the Controller where they are testable.

So, we are going to write Unit Tests for the two control methods we just created and the corresponding logic in the model.

First, we need to setup our testing environment. The default template already created a Test project we can start to customize.

1. In the MvcApplicationTest project, create a new class called ProductControllerTest.cs

2. Add a method for testing the Categories action we defined above.

namespace MvcApplicationTest.Controllers
{

    [TestClass]
    public class ProductsControllerTest
    {

        [TestMethod]
        public void Categories()
        {

        }
    }

3. We want to test the controller we wrote, but we don't want to load IIS and all of ASP.NET... we want to have the leanest, most simple system we can to avoid test breaks, etc. To that end, I created a test specific subclass of the ProductsController we defined above. In this subclass I override the RenderView method. Instead of calling out to ASP.NET, my test specific implement simply captures the arguments so they can be queried later in the test.

class TestProductsController : ProductsController
{
    public string ViewName { get; set; }
    public string MasterName { get; set; }
    public new object ViewData { get; set; }
    protected override void RenderView(string viewName, string masterName, object viewData)
    {
        ViewData = viewData;
        MasterName = masterName;
        ViewName = viewName;
    }
  }

4. Now we implement the test! First we create an instance of our test controller, then I create some dummy (or mock) data. The idea here is that we don't want to hit the production database (or any database for that mater) in our tests. We want exactly the data we need for the test, no more, no less. Then we set up the NorthwindDataContext to use our data rather than the data from the database. Then we call the controller action we are trying to test. Finally, we assert a few things.. that the type of the ViewData is right, that the number of items returned is right, etc. Notice, you will need to add a reference to the EntityFramework (System.Data.Entity.dll) in your test project to use these EF generated types like Product, Category, etc.

[TestMethod]
public void Categories()
{
    // Create Products Controller
    TestProductsController controller = new TestProductsController();

    List<Category> l = new List<Category>();
    l.Add(new Category() { CategoryName = "Drink" });
    l.Add(new Category() { CategoryName = "Food" });
    l.Add(new Category() { CategoryName = "Cheese" });

    controller.Northwind.TheCategories = l.AsQueryable();

    // Invoke Controller Action
    controller.Categories();

    // Verify Detail Action Behavior
    Assert.AreEqual(typeof(List<Category>),
                     controller.ViewData.GetType(),
                     "Product object Passed to View");

    Assert.AreEqual(3,
                     ((List<Category>)controller.ViewData).Count,
                     "Correct Number of Catagories returned");

    Assert.AreEqual("Food",
                     ((List<Category>)controller.ViewData)[1].CategoryName,
                     "Correct Product Object Passed to View");

    Assert.AreEqual("Categories",
                     controller.ViewName,
                     "Correct View Rendered");

}

5. Set the connection string in the test project so that it access the metadata from EF model, but does not open the database. In MVCApplicationTest add an app.config file to the root of the project with the this connection string.

<?xml version="1.0"?>
<configuration>
  <connectionStrings>
    <add name="NorthwindEntities"
         connectionString="metadata=res://*/;provider=System.Data.SqlClient;"
         providerName="System.Data.EntityClient" />
  </connectionStrings>
</configuration>

Now, we need to go back to the EDM designer and set it to embed the metadata for the model as part of the assembly. This makes our connection string above much more simple. Double click on the edmx file, then click on the conceptual model in the model browser and in the property sheet you change the property Metadata Artifact Processing from “Copy to Output Directory” to “Embed in Output Assembly”

6. Now we need to do just a bit of setup in the MVCApplication to enable a great testing experience... There are a few tricks here and what I am showing is NOT the definitive model (there isn't a definitive model yet)... but I like it, so what the heck!

MVCApplication/Model/NorthwindDataContext.cs add the following encapsulation of the Categories property.

private IQueryable<Product> savedProducts = null;
public IQueryable<Product> TheProducts
{
    get
    {
        if (savedProducts == null) savedProducts = this.Products;
        return savedProducts;
    }
    set
    {
        savedProducts = value;
    }
}

Then, make sure that all access go through this abstraction. For example:

public List<Product> GetProductsByCategory(string category)
{
    return TheProducts.Where(p => p.Category.CategoryName == category).ToList();
}

Finally, we need to make sure the NorthwindEntities is accessible from the test classes, so in ProductsController.cs add the "public" modifier.

public NorthwindEntities Northwind = new NorthwindEntities();

Now, we are able to run our test. You can do this by setting the test project as being the "startup project" (right click on the test project) or you can select Test/Run menu option.

Well, that is the lap around MVC+EF... There is a lot more to the sample I posted. If there is interest and I get the time, I will walk through the rest in future blog posts, but all the source code is there, so you can have fun with it on your own!

Enjoy!

You can download the full working example here (Updated to work with latest bits).

Software Development Predictions for 2008

BradA — Mon, 31 Dec 2007 19:06:27 GMT

Happy New Year!

Not too long ago, I was asked for my predictions for the IT-Technology in 2008... You can find the full article here, but I thought I'd include my thoughts on my blog.

Where's i-Technology Headed in 2008?

I'd love to hear your thoughts and comments

1. User Experience Reaches the Enterprise. In 2008 we will see several major enterprises start efforts to build UX centric applications that increase worker productivity, reduced transaction costs and increase pull through as the UX meme of the consumer facing world leaks into the enterprise. The days of the battleship gray, forms of data application as the king of the enterprise are numbered because of an imperative towards richer visualization of complex and interconnected data. While there will always be a need for the traditional sort of application, by the end of 2008, it is no longer the only element of the corporate landscape.

2. Testability Becomes a Requirement for Software Development Frameworks. No longer satisfied with simple reductions in costs for initial development, a growing community demand frameworks and tools that facilitate sustainable and agile practices. 2008 is the year that frameworks and tools take notice and start to deliver solutions that are testable out of the box. Technologies such as Test Driven Development, MVC/MVP patterns, and frameworks that support mocking become mainstream. After seeing this year’s cool demos at software development industry conferences a common question will be: “...And how do you test that?” Let’s hope the presenters have an answer.

3. The Companion Applications Become Practical. While RIA and AJAX application categories continue to grow, many consumer facing web applications and enterprise applications developers realize there is a need for desktop exploitive applications as well as reach web applications that work everywhere. What meaningful application wouldn’t benefit from a pairing like that of Outlook and Outlook Web Access? In the past it has been prohibitively expensive to build these applications, but with the circa 2008 technology such as .NET Framework 3.5 and Silverlight, it is finally becoming practical to have a single codebase that fully exploits the desktop and offers a rich web experience.

Results for Ajax usage among .NET developers

BradA — Sat, 22 Dec 2007 02:24:39 GMT

Simone Chiaretta recently posted the results to his Ajax usage survey.

Check out the: .NET Ajax Survey results

Simone has a great write up, including the raw data, I encourage you to check it out... But A couple of things that popped out to me:

1. Simone concludes that 84% of ASP.NET developers are using ASP.NET AJAX... That is an amazingly high percentage... I am excited that we could help that large a percentage of developers!

2. I am a bit surprised that only about ~50% of developers are using the AJAX Control Toolkit. I'd love to hear your thoughts on using the toolkit? Do you think it is a naming thing (people don't get the difference between ASP.NET AJAX and the AJAX toolkit?) or maybe it has to do with the heavy update panel usage, or are the factors that prevent developers from using the toolkit? Any theories?

3. Apparently, UpdatePanel kicks butt! 91.8% of ASP.NET AJAX users are using UpdatePanel. Personally, I love this feature as well. It gives you Ajax style of interactivity for your application without writing client side Ajax code!

4. Last but not least, I am absolutely amazed at the high early uptake of the ASP.NET MVC Framework. We are just a couple of weeks into our first public CTP and already 2.3% of folks said they are using it! That is way higher than i'd expect so early on. What is more, is that his a much higher percentage than any of the other, much more mature, MVC frameworks.

The Wait is Over: ASP.NET 3.5 Extensions Preview Posted

BradA — Mon, 10 Dec 2007 06:29:04 GMT

Ok, ok, it took us a little longer than we expected, but we finally got the ASP.NET 3.5 Extension Preview posted! This is the release with all the MVC goodness you have been hearing about as well as some very cool stuff such as Dynamic Data controls which makes building data driven web applications a breeze, AJAX history support, ADO.NET Data Services (aka Astoria), the ADO.NET Entity Framework and updated ASP.NET support for Silverlight.

Download the bits - they work with VS 2008 and are side-by-side so they will not hork your system

Check out the Quick Starts

Get Involved in the Forums

Here are a few links to get you going:

ScottGu has an excellent 4 part tutorial on building an MVC based application...
Phil Haack has some great info on his blog (he is the PM for MVC)
Rob Conery has some great stuff as well.. he is the author of the HTML helpers in the MVCToolkit.zip that adds a lot of cool gravy to the MVC stuff.
Oh, and now you can play with my MVC RSS sample
David Ebbo is the dev for the Dynamic Data controls and the author of the Oryx for MVC support in the MVCToolkit.zip.
Nikhil Kothari has some very cool AJAX\MVC work
Dave Reed has some good info on the ASP.NET Silverlight support, I am sure he will be updating it soon for this preview..
Some great info on Astoria.. I mean the ADO.NET Data Services ;-)
Bertrand Le Roy has some information on the AJAX support such as History.. I am sure he will be posting about this release soon as well.

RSS Feed with the new ASP.NET MVC Framework

BradA — Thu, 15 Nov 2007 09:28:00 GMT

I thought I'd add my own MVC example to the great work that ScottGu and Hanselman have already outlined... I know folks are ready to get their hands on these bits and believe me the team is working hard to get them out in a public CTP as soon as we can.. In the mean time, you will have to settle for these teasers ;-)

In this example, I am going to walk through building an RSS feed from data in a relational database.. My goal here is to give you and idea of what is possible with the MVC support that is coming out as a CTP soon for ASP.NET...

File/New Project and select the MVC Project item

There is some good stuff here, that really shows you how to get going... but for what we are going to do, we don't really need it... so go ahead and clear out all the directories and files under Views, Models and Controllers... we will build this from scratch.

Creating the Model

Because I had an existing database, I chose to start with it... I added my VideoDatabase.mdf file from another project I worked on recently.. of course any database would work. Then I created a Linq model and called it "VideoDatabase.dbml"... Notice of course EntityFramework would work really well here as well...

In the LINQ designer, I added the Items table to the design surface

and then moved the resulting VideoDatabase.dbml file to the Models directory... We now have our model done!

Creating the Controller

Next we add our controller which handles the UI logic of our application.. I click on the Controllers folder and Add new item

I called it FeedController, but remember, this has to end in Controller as there are some conventions we use to find these types.. I added the following code to get the list of items from the database and pass it to the view...

public class FeedController : Controller

{

//example: http://localhost:64701/

[ControllerAction]

public void Index()

{

VideoDatabaseDataContext context = new VideoDatabaseDataContext();

var list =

from item in context.Items

orderby item.Title

select item;

RenderView("Feed", list.ToList());

}
}

(note: be sure to add using MvcApplication.Models)

Creating the View

The view we want for an RSS feed is actually an not HTML... it is an XML file... but we want to programmatically generate it. I started by creating a new directory called "Feed" under "View" and added an MVC View Page called "Feed"...

Then I went to my blog and grabbed the RSS feed to use as an example. You can create a temporary XML file in VS to view it cleanly, then strip all but one entry... You will end up with something like this:

Next we need to parameterize this to use the data from our Model...

The first thing to do to enable that is to type the ViewData this page will work with.. you do that by going into the codebehind and setting the base class to be associated with the Item from our Model...

namespace MvcApplication.Views.Feed

{

public partial class Feed : ViewPage<IList<Item>>

{

}

(note: be sure to add using System.Collections.Generic and using MvcApplication.Models)

Then, back in the feed.aspx page, you can access the view data... right before the open <item> add the start of a foreach loop, then close it after the end...

<% foreach (Item item in this.ViewData) { %>

<item>

Then, replace each value with the appropriate data from the view programmatically...

What you end up with looks like this:

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Feed.aspx.cs" Inherits="MvcApplication.Views.Feed.Feed" %>

<%@ Import Namespace="MvcApplication.Models" %>

<%@ Import Namespace="System.Collections.Generic" %><?xml version="1.0" encoding="utf-8"?>

<title cf:type="text"> MySilverlightTV Feed</title>

<description cf:type="text">Check out the latest videos from MySilverlightTV</description>

<dc:language>en-US</dc:language>

<% foreach (Item item in this.ViewData) { %>

<item>

<%= item.Title %> </title>

<%= item.Description %>

</description>

</item>

<% } %>

</channel>

</rss>

Run it

We want to navigate to the Controller we created.. so navigate to http://localhost:64701/feed

and you get this beautiful RSS feed ready to work in any blog reader:

But there is more

Of course there is was only a few lines of code here, but really I could have done this just as easily, what does all that MVC stuff buy you? Well, a good architecture for one, and that means it is super flexible. So when you need to add a different feed, say the most popular items, or the new items added, or the top 10 items, it is very easy to do... Here are a few more items I added by only touching the controller, everything else stayed the same:

public class FeedController : Controller

{

//example: http://localhost:64701/

[ControllerAction]

public void Index()

{

VideoDatabaseDataContext context = new VideoDatabaseDataContext();

var list =

from item in context.Items

orderby item.Title

select item;

RenderView("Feed", list.ToList());

}

//example: http://localhost:64701/feed/Top10

[ControllerAction]

public void Top10()

{

VideoDatabaseDataContext context = new VideoDatabaseDataContext();

var list =

from item in context.Items

orderby item.Rating

select item;

RenderView("Feed", list.Take(10).ToList());

}

//example: http://localhost:64701/feed/Top?n=2

[ControllerAction]

public void Top(int n)

{

VideoDatabaseDataContext context = new VideoDatabaseDataContext();

var list =

from item in context.Items

orderby item.Rating

select item;

RenderView("Feed", list.Take(n).ToList());

}

//example: http://localhost:64701/feed/FromMSFT

[ControllerAction]

public void FromMSFT()

{

VideoDatabaseDataContext context = new VideoDatabaseDataContext();

var list =

from item in context.Items

orderby item.Title

where item.Owner == "MSFT"

select item;

RenderView("Feed", list.ToList());

}

//example: http://localhost:64701/feed/FromPublisher?Publisher=WildAmerica

[ControllerAction]

public void FromPublisher(string publisher)

{

VideoDatabaseDataContext context = new VideoDatabaseDataContext();

var list =

from item in context.Items

orderby item.Title

where item.Owner == publisher

select item;

RenderView("Feed", list.ToList());

}

What do you think? are we on the right track?