Category Archives: .net

Is this why it is Windows 10 (not 9): avoiding Windows 95 detection?

Why did Microsoft call the Windows release after 8 version 10 rather than 9?

Windows boss Terry Myerson said it was because it was such a huge release – but then he would say that.

A more prosaic reason could be the old software problem of false version detection. After all, we have had Windows 9x before – that is, Windows 95 and Windows 98.

Former Windows chief Steven Sinofsky tweeted this a few hours ago:

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which if you follow the link gets this:

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The first of these throws an exception if the name of the OS starts with “Windows 9”; and there are plenty of others like it.

Now, Windows version numbers are complex (Windows 95 actually reported itself as version 4.0) and well-written applications would get this right. There is also a year or so before Windows 10 is released, which gives time for developers, and the suppliers of runtimes like Java, to fix their code if necessary.

Still, it seems to me plausible that avoiding a version headache was a factor behind the naming of Windows 10.

Microsoft releases WinJS cross-browser JavaScript library but why?

Microsoft has announced WinJS 3.0:

The Windows Library for JavaScript (WinJS) project is pleased to announce the general availability of its first release – WinJS 3.0 – since the open source project began at //BUILD 2014.

Much of WinJS will run on any modern browser but the browser support matrix has a number of gaps:

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You can also see what runs where from this status table.

But what is WinJS? Note that it comes from the Windows apps team, not the web development team at Microsoft. WinJS was designed to enable app development for Windows 8 “Metro” (also known as the Windows Runtime) using JavaScript, CSS and HTML. Back in 2010, when Microsoft signalled the end of Silverlight and the rise of HTML 5 for browser-based applications, early versions of WinJS would already have been in preparation. Using WinJS you can share code across a Windows 8 app, web apps, and via an app packager like Apache Cordova, in apps for Android and iOS as well.

Note that Cordova is now integrated into Visual Studio, using the catchy name Multi-Device Hybrid App:

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If you want to know what kind of controls and components are on offer in WinJS, you can find out using the excellent demo site here. This is Firefox:

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Quick summary then: WinJS lets you build apps that look like Windows 8 Store apps, but which run cross-browser and cross-platform. But who wants to do that?

Maybe Microsoft does. The messaging from the company, especially since CEO Satya Nadella took over from Windows guy Steve Ballmer, is “any device”, provided of course that they hook up to Microsoft’s services. That messaging is intended for developers outside the company too. Check out the current campaign for Microsoft Azure, which says “consume on any device”.

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This could be a web application, or it could be a client app using Azure Mobile Services or an ASP.NET Web API application to connect to cloud data.

You do not have to use WinJS to consume Microsoft’s services of course. Why would developers want to use the look and feel of a rather unloved app platform, rather than the native look and feel of Android or iOS? That is an excellent question, and in most cases they will not. There could be cases though, for example for internal business apps where users care most about functionality. What is the current stock? What is the lead time? Show me this customer’s order history. A WinJS app might not look right for the platform, but the UI will be touch-friendly, and ease of rollout across the major mobile platforms could trump Apple’s design guidelines.

If you are writing a pure web application, users expectations concerning native look and feel are not so high. The touch-oriented design of WinJS is its main appeal, though other web frameworks like JQuery Mobile also offer this. The “Metro” design language is distinctive, and Microsoft will be making a renewed push for Windows Store apps, or Universal Apps, as part of the new wave of Windows called Windows 9 or “Threshold”. WinJS is the way to build apps for that platform using JavaScript and HTML, with the added bonus of easy porting to a broad range of devices.

This is a hard sell though. I am impressed by the effort Microsoft has put into making WinJS work cross-platform, but will be surprised to see much usage outside Windows Store apps (including Windows Phone). On the other hand, it does help to keep the code honest: this really is HTML and JavaScript, not just a wrapper for Windows Runtime APIs.

Lifetime registration as a Windows Store developer, now from £12

Microsoft has removed some friction from developing for the Windows Store (whether phone or Windows 8) by removing the requirement to pay an annual subscription:

As we continue to execute on the vision to integrate the Windows and Windows Phone developer experiences, we have taken another step by moving to a one-time lifelong Dev Center registration fee.

says Microsoft’s Todd Brix in a post today. He adds that the 600,000 developers already registered are covered, with no additional fee required.

How much is the fee? Brix does not say, and I could not find it quickly, so I started the signup process. I was offered individual registration for just £12.00. A company registration is £65.00.

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Both fees are of course negligible for a developer, compared to the cost of developing an app that is worth installing. Considering that Microsoft has had problems with junk apps filling its store, you could argue that fees are justifiable as a means of restraining the flow of meaningless or malicious apps.

The counter-argument is that fees deter developers from getting started, and that today’s hobbyist may come up with the next Minecraft. It is better to control quality with a robust checking process before apps are admitted into the store.

I had a quick glance today, and have the impression that Microsoft has made progress in removing the worst offenders, following some agitation at the end of last month.

Microsoft is laying the foundation for another go at its app platform with the launch of Windows 9, about which we will hear more in a couple of weeks time.

Microsoft integrates Azure websites with hybrid cloud

Microsoft has announced the integration of Azure websites with Azure virtual networks, including access to on-premise resources if you have a site-to-site VPN.

The Virtual Network feature grants your website access to resources running your VNET that includes being able to access web services or databases running on your Azure Virtual Machines. If your VNET is connected to your on premise network with Site to Site VPN, then your Azure Website will now be able to access on premise systems through the Azure Websites Virtual Network feature.

Azure websites let you deploy web applications running on IIS (Microsoft’s web server) hosted in Microsoft’s cloud. The application platform can be framework can be ASP.NET, Java, PHP, Node.js or Python. There are Free, Shared and Basic tiers which are mainly for prototyping, and a Standard tier which has auto-scaling features, managed through Microsoft’s web portal:

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The development tool is Visual Studio, which now has strong integration with Azure.

Integration with virtual networks is a significant feature. You could now host what is in effect an intranet application on Azure if it is convenient. If it is only used in working hours, say, or mainly used in the first couple of hours in the morning, you could scale it accordingly.

Have a look at that web configuration page above, and compare it with the intricacies of System Center. It is a huge difference and shows that some parts of Microsoft have learned that usability matters, even for systems aimed at IT professionals.

Windows “9”: forget the Start menu, consider the apps

This week has seen multiple leaks of early builds of the next version of Windows – sometimes called Windows 9 or “Threshold” – showing Microsoft’s continuing inability to persuade all of its partners to keep secrets.

It seems to me that the leaks are likely to be genuine, though the usual health warnings apply. I also expect that Microsoft is deliberately holding back from releasing final UI designs, in part because they are likely to leak, so you should not read too much into the appearance.

The headline new features are a revamped Start menu which appears in the old position on the desktop, rather than on a separate screen; and the ability to run several desktops at once, as a way of organising your work.

No doubt the new Start menu will feel more comfortable for Windows 7 users, though for myself I am now used to the full-screen version and it is no big deal.

I am more interested in what is happening with Windows Store apps (also known as Metro or Windows Runtime apps). These are significant because it is this kind of app that you can easily port to Windows Phone using a Visual Studio Universal App project.

We saw these apps running in desktop windows, in a preview at the Build developer conference earlier this year. The leaked build seems also to have this feature. Check out the video here. Here is Calculator running on the desktop:

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This is the Metro app, not the old desktop calculator. Here it is in Windows 8.1:

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Note a big difference though: in Windows 8.1 you can get a window bar to appear along the top, but in Windows 9 there is also a maximize widget at top right of the window (in Windows, this doubles as a “restore down” button when the windows is already maximized).

Later in the video, we see this in operation. The user starts the Xbox Video app full screen:

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and then hits the “restore down” button:

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This is therefore the bridge between the “Metro” and desktop environments. Hit that button, and the full-screen experience becomes a windowed app on the desktop.

In another leaked image, the Charms menu options (a right-edge menu in Windows 8.x) becomes a drop-down window menu, summoned by clicking in the right-hand upper corner. Users often find the Charms menu awkward with mouse and keyboard (I still do) so this will be a more convenient alternative.

Now, although Windows experts can easily see the difference between a Metro app and a desktop app, I doubt that the average user will care. All they will note is that this kind of app requires Windows 8 or 9 to run.

Although this is a diminished target for developers, who may still prefer to write desktop apps that target Windows 7 (or XP) and higher, my guess is that this new UI will make Windows Runtime apps more visible and acceptable for users who live primarily in the desktop – which is most Windows users.

If Microsoft can increase the momentum behind this style of apps, then their benefits will be more apparent too: easy install and uninstall via the Store, low malware risk, and a UI that works well on tablets as well as with mouse and keyboard. This in turn would make more sense of the small Windows tablets from the likes of Toshiba, HP and Lenovo which we recently saw at IFA in Berlin.

There would be a knock-on benefit for Windows Phone, too, thanks to relatively easy porting between the two platforms.

What do you think – is desktop integration enough to rescue the Windows 8 app platform?

Book review: Professional ASP.NET MVC 5. Is this the way to learn ASP.NET MVC?

This book caught my eye because while I like ASP.NET MVC, Microsoft’s modern web application framework, it seems to be badly documented. Even the word “badly” is not quite right; there is lots of documentation, some of high quality, but finding your way around it is challenging, thanks to the many different pieces involved. When I completed an ASP.NET MVC project recently, I found it frustrating thanks to over-reliance on sample projects (hey, here is a an application we did that works, see if you can figure out how we did it), many out of date articles relating to old versions; and the opposite, posts and samples which include preview software that does not seem wise to use in production.

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In my experience ASP.NET MVC is both cleaner and faster than ASP.NET Web Forms, the older .NET web framework, but there is more to learn before you can go ahead and write an application.

Professional ASP.NET MVC 5 gives you nearly 600 pages on the subject. It is aimed at a broad readership: the introduction states:

Professional ASP.NET MVC 5 is designed to teach ASP.NET MVC, from a beginner level through advanced topics.

Perhaps that is too broad, though the idea is that the first six chapters (about 150 pages) cover the basics, and that the later chapters are more advanced, so if you are not a beginner you can start at chapter 7.

The main author is Jon Galloway who is a Technical Evangelist at Microsoft. The other authors are Brad Wilson, formerly at Microsoft and now at CenturyLink Cloud; K Scott Allen at OdeToCode, David Matson who is on the ASP.NET MVC team at Microsoft, and Phil Haack formerly at Microsoft and now at GitHub. I get the impression that Haack wrote several chapters in an earlier edition of the book, but did not work directly on this one; Galloway brought his chapters up to date.

Be in no doubt: there are plenty of well-informed ASP.NET MVC people on this team.

The earlier part of the book uses a sample Music Store application, a version of which is publicly available here. You can also download a tutorial, based on the sample, written by Galloway. The public tutorial however dates from 2011 and is based on ASP.NET MVC 3 and Visual Studio 2010. The book uses Visual Studio 2013.

Chapters 1 to 6, the beginner section, do a decent job of talking you through how to build a first application. There are chapters on Controllers, Views, Models, Forms and HTML Helpers, and finally Data Annotations and Validation. It’s a good basic introduction but if you are like me you will come out with many questions, like what is an ActionResult (the type of most Controller methods)? You have to wait until chapter 16 for a full description.

Chapter 7 is on Membership, Authorization and Security. That is too much for one chapter. It is mostly on security, and inadequate on membership. One of my disappointments with this book is that Azure Active Directory hardly gets a mention; yet to my mind integration of web applications with Office 365 (which uses Azure AD) is a huge feature for Microsoft.

On security though, this is a useful chapter, with handy coverage of Cross-Site Request Forgery and other common vulnerabilities.

Next comes a chapter on AJAX with a little bit on JQuery, client-side validation, and Ajax ActionLinks. Here is the dilemma though. Does it make sense to cover JQuery in detail, when this very popular open source library is widely documented elsewhere? On the other hand, does it make sense not to cover JQuery in detail, when it is usually a vital part of your ASP.NET MVC application?

I would add that this title is poor on design aspects of a web application. That said, I was not expecting much on the design side; but what would help would be coverage of how to work with designers: what is safe to hand over to designers, and how does a typical designer/developer workflow play out with ASP.NET MVC?

I would also like to see more coverage of how to work with Bootstrap, the CSS framework which is integrated with ASP.NET MVC 5 in Visual Studio. I found it a challenge, for example, to discover the best way to change the default fonts and colours used, which is rather basic.

Chapter 9 is on routing, dry but essential background. Chapter 10 on NuGet, the Visual Studio package manager, and a good chapter given how important NuGet now is for most Visual Studio work.

Incidentally, many of the samples for the book can be installed via NuGet. It’s not completely obvious how to do this. I found the best way is to go to http://www.nuget.org and search for Wrox.ProMvc5 – here is the link to the search results. This lists all the packages available; note the package names. Then open the Nuget package manager console and type:

install-package [packagename]

to get the sample.

Chapter 11 is a too-brief chapter on the Web API. I would like to see more on this, maybe even walking through a complete application with clients for say, Windows Phone and a web application – though the following chapter does present a client example using AngularJS.

Chapter 13 is a somewhat theoretical look at dependency injection and inversion of control; handy as Microsoft developers talk a lot about this.

Next comes a very brief introduction to unit testing, intended I think only as a starting point.

For me, the the next two chapters are the most valuable. Chapter 15 concerns extending MVC: you learn about extending models with value providers and model binders; validating models; writing HTML helpers and Razor (the view engine in ASP.NET MVC) helpers; authentication filters and authorization filters. Chapter 16 on advanced topics looks in more detail at Razor, routing, templates, ActionResult and a few other things.

Finally, we get a look at how the Nuget.org application was put together, and an appendix covering some miscellaneous details like what is new in ASP.NET MVC 5.1.

Conclusions

I find this one hard to summarise. There is too much missing to give this an unreserved recommendation. I would like more on topics including ASP.NET Identity, Azure AD integration, Entity Framework, Bootstrap, and more. Trying to cover every developer from beginner to advanced is too much; removing some of the introductory material would have left more room for the more interesting sections. The book is also rather weighted towards theory rather than hands-on coding. At some points it felt more like an explanation from the ASP.NET MVC team on “why we did it this way”, than a developer tutorial.

That said, having those insights from the team is valuable in itself. As someone who has only recently engaged with ASP.NET MVC in a real application, I did find the book useful and will come back to some of those explanations in future.

Looking at what else is available, it seems to me that there is a shortage of books on this subject and that a “what you need to know” title aimed at professional developers would be widely welcomed. It would pay Microsoft to sponsor it, since my sense is that some developers stick with ASP.NET Web Forms not because it is better, but because it is more approachable.

 

Microsoft introduces a new 2D graphics API for the Windows Runtime

Microsoft has announced Win2D, a Windows Runtime API that wraps Direct2D (part of DirectX), for accelerated graphics in Windows Store apps.

The new API is described here and you can download the current binary here. It is in its early stages, but already supports basic drawing, bitmap loading, some image effects, and a vector and matrix math library. Here is some sample code:

void canvasControl_Draw(CanvasControl sender, CanvasDrawEventArgs args)
{
args.DrawingSession.Clear(Colors.CornflowerBlue);
args.DrawingSession.DrawEllipse(190, 125, 140, 40, Colors.Black, 6);
args.DrawingSession.DrawText("Hello, world!", 100, 100, Colors.Yellow);
}

Although this hardly looks exciting, it is important because it enables accelerated custom drawing from languages other than C++, and without needing to learn Direct2D itself. It will be easier to make rich custom controls, or casual 2D games.

That said, there are already alternative C# wrappers for DirectX in Windows Runtime apps, such as SharpDX.

Some of the comments on the MSDN post are sceptical:

Managed DirectX and XNA were however cancelled despite the frustration from the community which in response created open source alternatives to save the projects and customers that had invested in technology Microsoft introduced.

I understand that the future is "uncertain", but is this technology something that we should dare invest in or will it see the same fate as it’s earlier incarnations?

Microsoft’s Shawn Hargreaves assures:

Win2D is absolutely not a side project or some kind of stop gap that will later be replaced by anything different.

The target here is universal apps, so not just Windows Store apps but also Windows Phone. Despite the hesitant reception for the Windows Runtime in Windows 8, it looks as if Microsoft is still committed to the platform and that it will remain centre stage in Windows vNext.

Bing Developer Assistant adds code samples to Visual Studio IntelliSense, with mixed results

Microsoft has updated its Bing Developer Assistant Beta, a Visual Studio 2013 add-in which hooks into IntelliSense so that you get code samples as well as brief documentation. For example, in an Entity Framework project, if you select dbContext.SaveChanges, you get a code sample which uses that method.

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There is no guarantee of course that the sample is relevant to what you are trying to accomplish. You can hit Search More though and get a selection of code snippets and sample projects, drawn from sites including MSDN, StackOverflow and Codeproject.

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Developer beware though. Looking at the code samples, the top one is from a 2011 blog post relating to CTP (Community Tech Preview) 5 of Entity Framework 4.1. If you hit the link, you get this:

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“The information in this post is out of date”, it says, followed by a link to what is in fairness a rather helpful article on using SaveChanges.

Hmm, maybe Bing Developer Assistant should try filtering the search to eliminate samples on preview or obsolete APIs? A snag here though is that on occasion the blogs and samples on preview frameworks are all you can get, because by the time the thing is actually released, the developer evangelists have move on to blog about the next up and coming cool thing.

If you choose an object member for which Bing finds no code sample, you are prompted to add one of your own:

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This takes to to the Developer Network sample upload page:

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This form is quite a lot of work, but lets you add a code snippet or sample project together with title and comments explaining what it does.

The Bing Developer Assistant also searches for sample projects:

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Again it is a case of picking and choosing what is really relevant; but developers are experts and expected to use common sense.

A drawback with Bing Developer Assistant is that only one add-on can extend IntelliSense, so if you use Resharper or another tool which also does this, you have to choose which one to allow.

In the end, this is all about integrating web search into the IDE. Is that a good idea, or is it better simply to have your web browser open, perhaps on another display, and type “dbContext SaveChanges EF6” or some such into your favourite search engine?

There is some merit in a search engine that automatically filters to show only code samples – hey, that is what Google’s popular Code Search did, until it was mysteriously shut down – though I’m not sure how much I like the idea of possibly obsolete and deprecated samples showing up in Visual Studio as you are coding.

Still, the truth is that web search is critical to software development today and it is good to see that recognised.

Developing an app on Microsoft Azure: a few quick reflections

I have recently completed (if applications are ever completed) an application which runs on Microsoft’s Azure platform. I used lots of Microsoft technology:

  • Visual Studio 2013
  • Visual Studio Online with Team Foundation version control
  • ASP.NET MVC 4.0
  • Entity Framework 4.0
  • Azure SQL
  • Azure Active Directory
  • Azure Web Sites
  • Azure Blob Storage
  • Microsoft .NET 4.5 with C#

The good news: the app works well and performance is good. The application handles the upload and download of large files by authorised users, and replaces a previous solution using a public file sending service. We were pleased to find that the new application is a little faster for upload and download, as well as offering better control over user access and a more professional appearance.

There were some complications though. The requirement was for internal users to log in with their Office 365 (Azure Active Directory) credentials, but for external users (the company’s customers) to log in with credentials stored in a SQL Server database – in other words, hybrid authentication. It turns out you can do this reasonably seamlessly by implementing IPrincipal in a custom class to support the database login. This is largely uncharted territory though in terms of official documentation and took some effort.

Second, Microsoft’s Azure Active Directory support for custom applications is half-baked. You can create an application that supports Azure AD login in a few moments with Visual Studio, but it does not give you any access to metadata like to which security groups the user belongs. I have posted about this in more detail here. There is an API of course, but it is currently a moving target: be prepared for some hassle if you try this.

Third, while Azure Blob Storage itself seems to work well, most of the resources for developers seem to have little idea of what a large file is. Since a primary use case for cloud storage is to cover scenarios where email attachments are not good enough, it seems to me that handling large files (by which I mean multiple GB) should be considered normal rather than exceptional. By way of mitigation, the API itself has been written with large files in mind, so it all works fine once you figure it out. More on this here.

What about Visual Studio? The experience has been good overall. Once you have configured the project correctly, you can update the site on Azure simply by hitting Publish and clicking Next a few times. There is some awkwardness over configuration for local debugging versus deployment. You probably want to connect to a local SQL Server and the Azure storage emulator when debugging, and the Azure hosted versions after publishing. Visual Studio has a Web.Debug.Config and a Web.Release.Config which lets you apply a transformation to your main Web.Config when publishing – though note that these do not have any effect when you simply run your project in Release mode. The correct usage is to set Web.Config to what you want for debugging, and apply the deployment configuration in Web.Release.Config; then it all works.

The piece that caused me most grief was a setting for <wsFederation>. When a user logs in with Azure AD, they get redirected to a Microsoft site to log in, and then back to the application. Applications have to be registered in Azure AD for this to work. There is some uncertainty though about whether the reply attribute, which specifies the redirection back to the app, needs to be set explicitly or not. In practice I found that it does need to be explicit, otherwise you get redirected to the deployed site even when debugging locally – not good.

I have mixed feelings about Team Foundation version control. It works, and I like having a web-based repository for my code. On the other hand, it is slow, and Visual Studio sulks from time to time and requires you to re-enter credentials (Microsoft seems to love making you do that). If you have a less than stellar internet connection (or even a good one), Visual Studio freezes from time to time since the source control stuff is not good at working in the background. It usually unfreezes eventually.

As an experiment, I set the project to require a successful build before check-in. The idea is that you cannot check in a broken build. However, this build has to take place on the server, not locally. So you try to check in, Visual Studio says a build is required, and prompts you to initiate it. You do so, and a build is queued. Some time later (5-10 minutes) the build completes and a dialog appears behind the IDE saying that you need to reconcile changes – even if there are none. Confusing.

What about Entity Framework? I have mixed feelings here too, and have posted separately on the subject. I used code-first: just create your classes and add them to your DbContext and all the data access code is handled for you, kind-of. It makes sense to use EF in an ASP.NET MVC project since the framework expects it, though it is not compulsory. I do miss the control you get from writing your own SQL though; and found myself using the SqlQuery method on occasion to recover some of that control.

Finally, a few notes on ASP.NET MVC. I mostly like it; the separation between Razor views (essentially HTML templates into which you pour your data at runtime) and the code which implements your business logic and data access is excellent. The code can get convoluted though. Have a look at this useful piece on the ASP.NET MVC WebGrid and this remark:

grid.Column("Name",
  format: @<text>@Html.ActionLink((string)item.Name,
  "Details", "Product", new { id = item.ProductId }, null)</text>),

The format parameter is actually a Func, but the Razor view engine hides that from us. But you’re free to pass a Func—for example, you could use a lambda expression.

The code works fine but is it natural and intuitive? Why, for example, do you have to cast the first argument to ActionLink to a string for it to work (I can confirm that it is necessary), and would you have worked this out without help?

I also hit a problem restyling the pages generated by Visual Studio, which use the twitter Bootstrap framework. The problem is that bootstrap.css is a generated file and it does not make sense to edit it directly. Rather, you should edit some variables and use them as input to regenerate it. I came up with a solution which I posted on stackoverflow but no comments yet – perhaps this post will stimulate some, as I am not sure if I found the best approach.

My sense is that what ASP.NET MVC is largely a thing of beauty, it has left behind more casual developers who want a quick and easy way to write business applications. Put another way, the framework is somewhat challenging for newcomers and that in turn affects the breadth of its adoption.

Developing on Azure and using Azure AD makes perfect sense for businesses which are using the Microsoft platform, especially if they use Office 365, and the level of integration on offer, together with the convenience of cloud hosting and anywhere access, is outstanding. There remain some issues with the maturity of the frameworks, ever-changing libraries, and poor or confusing documentation.

Since this area is strategic for Microsoft, I suggest that it would benefit the company to work hard on pulling it all together more effectively.

Should you use Entity Framework for .NET applications?

I have been working on a project which I thought would be simpler than it turned out to be – nothing new there, most software projects are like that.

The project involves upload and download of large files from Azure storage. There is a database as part of the application, nothing too demanding, but requiring some typical CRUD (Create, Retrieve, Update, Delete) functionality. I had to decide how to implement this.

First, a confession. I am comfortable using SQL and my normal approach to a database application is to use ADO.NET DataReaders to read data. They are brilliant; you just send some SQL to the database and back comes the data in a format that is easy to read back in C# code.

When I need to update the data, I use SqlCommand.ExecuteNonQuery which executes arbitrary SQL. It is easy to use parameters and transactions, and I get full control over how many connections are open and so on.

This approach has always worked well for me and I get excellent performance and complete flexibility.

However, when coding in ASP.NET MVC and Visual Studio you are now steered firmly towards Entity Framework (EF), Microsoft’s object-relational mapping library. You can use a code-first approach. Simply create a C# class for the object you want to store, and EF handles all the drudgery of creating tables and building SQL queries, letting you concentrate on the unique features of your application.

In addition, you can right-click in the Solution Explorer, choose Add Controller, and a wizard will generate all the code for listing, creating, editing and deleting those objects.

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Well, that is the idea, and it does work, but I soon ran into issues that made me wonder if I had made the right decision.

One of the issues is what happens when you change your mind. Maybe that field should be an Int rather than a String. Maybe you need a second phone number field. Maybe you need to create new tables. How do you keep the database in synch with your classes?

This is called Code First Migrations and involves running commands that work out how the database needs to change and generates code to update it. It’s clever stuff, but the downside is that I now have a bunch of generated classes and a generated _MigrationHistory table which I did not need before. In addition, something when slightly wrong in my case and I ended up having to comment out some of the generated code in order to make the migration work.

At this point EF is creating work for me, rather than saving it.

Another issue I encountered was puzzling out how to do stuff beyond the most trivial. How do you replace an HTML edit box with a dropdown list? How do you exclude fields from being saved when you call dbContext.SaveChanges? What is the correct way to retrieve and modify data in pure code, without data binding?

I am not the first to have questions. I came across this documentation: an article promisingly entitled How to: Add, Modify, and Delete Objects which tells you nothing of value. Spot how many found it helpful:

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You should probably start here instead. Still, be aware that EF is by no means straightforward. Instead of having to know SQL and the basics of ADO.NET commands and DataReaders, you now have to know EF, and I am not sure it is any less intricate. You also need to be comfortable with data binding and LINQ (Language Integrated Query) to make sense of it all, though I will add that strong data binding support is one reason whey EF is a good fit for ASP.NET MVC.

Should you use Entity Framework? It remains, as far as I can tell, the strategic direction for data access on Microsoft’s platform, and once you have worked out the basics you should be able to put together simple database applications more quickly and more naturally than with manually coded SQL.

I am not sure it makes sense for heavy-duty data access, since it is harder to fine-tune performance and if you hit subtle bugs, you may end up in the depths of EF rather than debugging your own code.

I would be interested in hearing from other developers. Do you love EF, avoid it, or is it just about OK?