CSLA .NET 3.8.4 is now available as a beta download. This is mostly a bug fix release to address a few issues from 3.8.3, plus some ASP.NET MVC work.

Version 3.8.4 targets .NET 3.5 and Silverlight 3 (though with a little effort it works with Silverlight 4 as well).

See the change log for a list of changes. There aren’t many, but if they affect you then they are important.

The only feature change in 3.8.4 is that most of the new ASP.NET MVC 2 support from CSLA 4 has been back-ported to 3.8. This means that the Csla.Web.Mvc project now targets and supports ASP.NET MVC 2, and provides more features and functionality that was there in 3.8.3.

• Download for Windows
• Download for Silverlight

This is a stable beta, given the small number of changes (other than the MVC support). So if you are affected by any of the issues listed in the change log I strongly recommend moving from 3.8.3 to 3.8.4 beta to test and utilize the changes.

I’m often asked whether CSLA .NET supports the MVC, MVP, MVVM or other “M” patterns.

The answer is an absolute YES! Of course it does, because CSLA .NET is all about the “M”.

The “M” in all these patterns stands for Model – the business layer that is supposed to encapsulate all your business logic and the data required for that logic to work.

Since its inception 13+ years ago, CSLA has been primarily focused on helping people build a powerful business layer composed of business domain objects. This implies strong separation of concerns where UI issues are (as much as possible) kept out of the business layer, as are data access concerns.

The various “M” patterns also support separation of concerns. Their perspective is from the UI level, as they are all UI patterns. But at the core of each of them is the idea that the “M” should encapsulate all the business logic, business processing and data required to perform that processing.

Whether you want a Controller-View or a Presenter-View or a View-ViewModel to organize your UI code, in every case you need a clearly separate Model against which the UI will work.

CSLA .NET 3.8 specifically added a bunch of features to simplify the use of MVVM in Silverlight and WPF, but that’s just simplification. MVVM worked fine without those enhancements, it is just a little easier now. Of course you still need an MVVM UI framework, because CSLA isn’t about the UI, it is about the Model.

CSLA .NET 3.8.2 includes a CslaModelBinder for ASP.NET MVC. Again, this simplifies one aspect of using ASP.NET MVC for your UI framework, but it isn’t strictly necessary – it just makes life easier. The same rule applies, CSLA isn’t a UI framework and so does as little as possible at the “V” and “C” level because its focus is all about the “M”.

Of course I’m referring to Windows Forms, which is about 8 years old. Even in dog years that’s not old. But in software years it is pretty old I’m afraid…

I’m writing this post because here and in other venues I’ve recently referred to Windows Forms as “legacy”, along with asmx and even possibly Web Forms. This has caused a certain amount of alarm, but I’m not here to apologize or mollify.

Technologies come and go. That’s just life in our industry. I was a DEC VAX guy for many years (I hear Ted Neward laughing now, he loves these stories), but I could see the end coming years before it faded away, so I switched to the woefully immature Windows platform (Windows 3.0 – what a step backward from the VAX!). I know many FoxPro people who transitioned, albeit painfully, to VB or other tools/languages. The same with Clipper/dBase/etc. Most PowerBuilder people transitioned to Java or .NET (though much to my surprise I recently learned that PowerBuilder still actually exists – like you can still buy it!!).

All through my career I’ve been lucky or observant enough to jump ship before any technology came down on my head. I switched to Windows before the VAX collapsed, and switched to .NET before VB6 collapsed, etc. And honestly I can’t think of a case where I didn’t feel like I was stepping back in time to use the “new technology” because it was so immature compared to the old stuff. But every single time it was worth the effort, because I avoided being trapped on a slowly fading platform/technology with my skills becoming less relevant every day.

But what is “legacy”? I once heard a consultant say “legacy is anything you’ve put in production”. Which might be good for a laugh, but isn’t terribly useful in any practical sense.

I think “legacy” refers to a technology or platform that is no longer an area of focus or investment by the creator/maintainer. In our world that mostly means Microsoft, and so the question is where is Microsoft focused, where are they spending their money and what are they enhancing?

The answers are pretty clear:

• Azure
• Silverlight
• ASP.NET MVC
• WPF (to a lesser degree)
• ADO.NET EF
• WCF

These are the areas where the research, development, marketing and general energy are all focused. Ask a Microsoft guy what’s cool or hot and you’ll hear about Azure or Silverlight, maybe ADO.NET EF or ASP.NET MVC and possibly WPF or WCF. But you won’t hear Windows Forms, Web Forms, asmx web services, Enterprise Services, Remoting, LINQ to SQL, DataSet/TableAdapter/DataTable or numerous other technologies.

Some of those other technologies aren’t legacy – they aren’t going away, they just aren’t sexy. Raw ADO.NET, for example. Nobody talks about that, but ADO.NET EF can’t exist without it, so it is safe. But in theory ADO.NET EF competes with the DataSet (poorly, but still) and so the DataSet is a strong candidate for the “legacy” label.

Silverlight and WPF both compete with Windows Forms. Poor Windows Forms is getting no love, no meaningful enhancements or new features. It is just there. At the same time, Silverlight gets a new release in less than 12 month cycles, and WPF gets all sorts of amazingly cool new features for Windows 7. You tell me whether Windows Forms is legacy. But whatever you decide, I’m surely spending zero cycles of my time on it.

asmx is obvious legacy too. Has been ever since WCF showed up, though WCF’s configuration issues have been a plague on its existence. I rather suspect .NET 4.0 will address those shortcomings though, making WCF as easy to use as asmx and driving the final nail in the asmx coffin.

Web Forms isn’t so clear to me. All the buzz is on ASP.NET MVC. That’s the technology all the cool kids are using, and it really is some nice technology – I like it as much as I’ll probably ever like a web technology. But if you look at .NET 4.0, Microsoft has done some really nice things in Web Forms. So while it isn’t getting the hype of MVC, it is still getting some very real love from the Microsoft development group that owns the technology. So I don’t think Web Forms is legacy now or in .NET 4.0, but beyond that it is hard to say. I strongly suspect the fate of Web Forms lies mostly in its user base and whether they fight for it, whether they make Microsoft believe it continues to be worth serious investment and improvement into the .NET 5.0 timeframe.

For my part, I can tell you that it is amazingly (impossibly?) time-consuming to be an expert on 7-9 different interface technologies (UI, service, workflow, etc). Sure CSLA .NET supports all of them, but there are increasing tensions between the stagnant technologies (most notably Windows Forms) and the vibrant technologies like Silverlight and WPF. It is no longer possible, for example, to create a collection object that works with all the interface technologies – you just can’t do it. And the time needed to deeply understand the different binding models and subtle differences grows with each release of .NET.

CSLA .NET 4.0 will absolutely still support all the interface technologies. But it would be foolish to cut off the future to protect the past – that way lies doom. So in CSLA .NET 4.0 you should expect to see support for Windows Forms still there, but probably moved into another namespace (Csla.Windows or something), while the main Csla namespace provides support for modern interface technologies like WPF, ASP.NET MVC, Silverlight, etc.

I am absolutely committed to providing a window of time where Windows Forms users can migrate their apps to WPF or Silverlight while still enjoying the value of CSLA .NET. And I really hope to make that reasonably smooth – ideally you’ll just have to change your base class types for your business objects when you switch the UI for the object from Windows Forms to XAML – though I suspect other minor tweaks may be necessary as well in some edge cases.

But let’s face it, at some point CSLA .NET does have to drop legacy technologies. I’m just one guy, and even with Magenic being such a great patron it isn’t realistic to support every technology ever invented for .NET :)  I don’t think the time to drop Windows Forms is in 4.0, because there are way too many people who need to migrate to WPF over the next 2-3 years.

On the other hand, if you and your organization aren’t developing a strategy to move off Windows Forms in the next few years I suspect you’ll eventually wake up one day and realize you are in a bad spot. One of those spots where you can’t hire anyone because no one else has done your technology for years, and nobody really remembers how it works (or at least won’t admit they do unless you offer them huge sums of money).

I don’t see this as bad. People who want stability shouldn’t be in computing. They should be in something like accounts receivable or accounts payable – parts of business that haven’t changed substantially for decades, or perhaps centuries.

I recently installed the latest version of IE8, bowing to pressure from some of my Microsoft colleagues :)

I don’t regret the decision! IE8 is easily as fast as FF3, and has a lot of really nice, often subtle, features that make it far more useful than IE7.

I was rather excited when I first went to my home page (www.lhotka.net), because it rendered correctly. This page renders nice in FF2, FF3 and now IE8. But it never quite worked right in IE7. I was never able to justify the (probably many) hours it would take to troubleshoot the css. Just getting my site working as well as it does was enough to turn my antipathy toward web UI work into tangible dislike.

(I know some people enjoy web UI work. I’ve only found it to be one of the most frustrating experiences in all the years I’ve been programming… Seriously – could we have invented anything more arcane??)

Anyway, my home page renders nicely in IE8, so I’m excited.

Until I try to navigate using one of the drop-down menus. All that appears is a while box! How can IE8 not render an ASP.NET Menu control?!?!?!?!?!

Well, it turns out that this is a known issue that the IE8 and ASP.NET teams are working on. It also turns out that it is apparently a z-order issue with the Menu control and the way it renders, so it can be argued that IE8 is actually doing the “right thing” (even though other browsers, including FF3 render the way I’d expect).

In talking to Joshua, Brad and Giorgio at Microsoft a workaround came to light, and Giorgio blogged the ASP.NET Menu control workaround.

I just had time to try this on my site. I’ll save you the suspense and say that it now does render correctly :)

In my case, I’m using themes and skins, and so I am using a css style to fix the z-order.

To do this, I added the workaround to my site-wide css style sheet:

.IE8Fix
{
    z-index: 1000;

}

And then I edited my skin file to apply this style to all my Menu controls:

<asp:Menu runat="server" BackColor="#83B8E4"

...
  <DynamicMenuStyle BackColor="#B5C7DE" CssClass="IE8Fix" />
...

</asp:Menu>

This was easy for me, because I already had the skin set up to apply numerous other properties and styles to the elements of the Menu control. I simply added the CssClass property to the existing DynamicMenuStyle element.

I published the project to my web server and just like that my Menu control is displaying correctly in IE8.

I'm just back from the MIX 08 conference. This was the first conference I've attended in many years (around 10 I think) where I wasn't speaking or somehow working. I'd forgotten just how fun and inspiring it can be to simply attend sessions and network with people in the open areas. No wonder people come to conference!! :)

Not that it was all fun and games. I did have meetings with some key Microsoft people and Scott Hanselman interviewed me for an upcoming episode of Hanselminutes (discussing the various data access and ORM technologies and how they relate to CSLA .NET 3.5).

The Day 1 keynote was everything I'd hoped for.

Well, nearly. The first part of the keynote was Ray Ozzie trying to convey how Microsoft and the web got to where it is now. The goal was to show the vision they are pursuing now and into the future, but I thought the whole segment was rather flat.

But then Scott Guthrie came on stage and that was everything you could hope for. Scott is a great guy, and his dedication and openness seem unparalleled within Microsoft. I remember first meeting him when ASP.NET was being unveiled. At that time he seemed so young and enthusiastic, and he was basically just this kick-ass dev who'd created the core of something that ultimately changed the Microsoft world. Today he seems nearly as young and easily as enthusiastic, and he's overseeing most of the cool technologies that continue to change the Microsoft world. Awesome!

So ScottGu gets on stage and orchestrates a keynote that really illustrates the future of the web. Silverlight (which makes me SOOoooo happy!), IE8, new data access technologies (like we needed more, but they are still cool!) and things like ASP.NET MVC and more.

As I expected, they released a whole lot of beta code. You can get a full list with links from Tim Sneath's blog. He also has links to some getting started materials.

The real reason for keynotes though, is to inspire. And this keynote didn't disappoint. The demos of Silverlight and related technologies were awesome! There was some funny and cute banter with the casting director from Circ del Sole as she demonstrated using a cool disconnected WPF app. There was a fellow RD, Scott Stanfield, showing integration of SeaDragon into Silveright so we can look (in exquisite detail) at the memorabilia owned by the Hard Rock Cafe company, some thought-provoking demos of Silverlight on mobile devices and more.

Now to be honest, I've never been a fan of the web development model. Having done terminal-based programming for many years before coming to Windows, I find it hard to get excited about returning to that ancient programming model. Well, a worse one actually, because at least the mainframe/minicomputer world had decent state management...

AJAX helps, but the browser makes for a pretty lame programming platform. It is more comparable perhaps to an Apple II or a Commodore 64 than to a modern environment, and that's before you get into the inconsistencies across browsers and that whole mess. Yuck!

Which is why Silverlight is so darn cool! Silverlight 2.0 is really a way to do smart client development with a true web deployment model. Much of the power of .NET and WPF/XAML, with the transparent deployment and cross-platform capabilities of the browser world. THIS is impressive stuff. To me Silverlight represents the real future of the web.

It should come as no surprise then, that I spent my time in Silverlight 2.0 sessions after the keynote. Sure, I've been working (on and off) with Silverlight 1.1/2.0 for the past several months, but it was a lot of fun to see presentations by great speakers like Joe Stegman (a Microsoft PM) and various other people.

One of the best sessions was on game development with Silverlight. I dabble in game development whenever I have spare time (not nearly as much as I'd like), and so the talk was interesting from that perspective. But many of the concepts and techniques they used in their games are things designers and developers will likely use in many other types of application. Background loading of assemblies and content while the app is running, and some clever animation techniques using pure XAML-based concepts (as opposed to some other animation techniques I saw that use custom controls written in C#/VB - which isn't bad, but it was fun to see the pure-XAML approaches).

Many people have asked about "CSLA Light", my planned version of CSLA .NET for Silverlight. Now that we have a Beta 1 of Silverlight I'll be working on a public release of CSLA Light, based on CSLA .NET 3.5. Microsoft has put a lot more functionality into Silverlight 2.0 than they'd originally planned - things like data binding, reflection and other key concepts are directly supported. This means that the majority of CSLA can be ported (with some work) into Silverlight. The data portal is the one big sticking point, and I'm sure that'll be the topic of future blog posts.

My goal is to support the CSLA .NET 3.5 syntax for property declaration and other coding constructs such that with little or no change you can take a business class from full CSLA and have it work in CSLA Light. This goal excludes the DataPortal_XZY implementations - those will almost always be different, though if you plan ahead and use a DTO-based data access model even that code may be the same. Of course time will tell how closely I'll meet this goal - but given my work with pre-beta Silverlight 2.0 code I think it is pretty realistic.

Scott Guthrie indicated that Silverlight 2.0 Beta 1 has a non-commercial go-live license - right now. And that Beta 2 would be in Q2 (I'm guessing June) and would have a commercial go-live license, meaning it can be used for real work in any context.

The future of the web is Silverlight, and Beta 1 is the start of that future. 2008 is going to be a great year!

I reader recently sent me an email asking why the PTWebService project in the CSLA .NET ProjectTracker reference app has support for using the data portal to talk to an application server. His understanding was that web services were end points, and that they should just talk to the database directly. Here's my answer:

A web service is just like any regular web application. The only meaningful difference is that it exposes XML instead of HTML.

Web applications often need to talk to application servers. While you are correct – it is ideal to build web apps in a 2-tier model, there are valid reasons (mostly around security) why organizations choose to build them using a 3-tier model.

The most common scenario (probably used by 40% of all organizations) is to put a second firewall between the web server and any internal servers. The web server is then never allowed to talk to the database directly (for security reasons), and instead is required to talk through that second firewall to an app server, which talks to the database.

The data portal in CSLA .NET helps address this issue, by allowing a web application to talk to an app server using several possible technologies. Since different organizations allow different technologies to penetrate that second firewall this flexibility is important.

Additionally, the data portal exists for other scenarios, like Windows Forms or WPF applications. It would be impractical for me to create different versions of CSLA for different types of application interface. In fact that would defeat the whole point of the framework – which is to provide a consistent and unified environment for building business layers that support all valid interface types (Windows, Web, WPF, Workflow, web service, WCF service, console, etc).

As long as I'm doing simple blog links, here's another tool worth looking at, if you need to skin a SharePoint or other web site: 

SharePoint Skinner Overview - eLumenotion Blog

In a recent entry there was a comment pointing to this article, which discusses the way ASP.NET uses threads – a fact that has serious ramifications on software design.

It made me do some serious thinking/research, because CSLA .NET uses various elements of the Thread object, including the CurrentPrincipal, thread-local storage and (in 2.0) the culture properties. My fear was that if the thread can switch “randomly” during page processing, then how can you count on any of these elements from the Thread object?

Scott Guthrie from Microsoft clarified this for me on a couple key points.

First, ASP.NET doesn’t change your thread at “random” or “without warning” (phrases I’d used in describing my worries). It changes it only in a clearly defined scenario. Specifically, when your thread performs an async IO operation. Scott points out that this is perhaps most common in a page that takes advantage of the new async page capability, or within a HttpModule that uses any async IO.

In other words, normal web pages really aren’t subject to this issue at all. It only occurs in relatively advanced scenarios. And you, as the developer, should know darn well when you invoke an async operation; thus you know when you open yourself up for thread switching.

Still, I wanted to make sure the Business Objects book didn’t go down a bad path with the Thread object. But Scott clarified further.

ASP.NET ensures that, even if they switch your thread, the CurrentPrincipal and culture properties from the original thread carry forward to the new thread. This is automatic, and you don’t need to worry about losing those values. Whew!

However, thread-local storage doesn’t carry forward. If you use that feature of the Thread object in ASP.NET code you could be in trouble. This did cause me to rework some code in the book and in CSLA .NET. Specifically CSLA .NET 2.0 now detects whether it is running in ASP.NET or not and uses either thread-local storage or HttpContext.Current.Items to maintain its context data.

I also went the rest of the way and created a Csla.ApplicationContext.User property that gets and sets the user’s principal on either the Thread or HttpContext based on whether the code is running in ASP.NET or not. This allows you to write code in your UI and objects and other libraries without worrying about whether it might run inside our outside ASP.NET at some point.

Certainly for mobile business objects this is very important! They can (and often do) run in both a smart client and ASP.NET environment within the same application.

The ADO Guy expresses his frustration that the ObjectDataSource doesn't work with typed DataSets in ADO.NET 2.0. In an earlier post I expressed my frustration about using it with business objects.

In the case of CSLA .NET 2.0 I'm writing my own CslaDataSource that understands how to work nicely with CSLA .NET business objects. In conferring with the ASP.NET team it seems like this is the best option. It turns out that writing a DataSource control isn't overly difficult - it is writing the designer support (for VS 2005) that is the hard part...

ASP.NET 2.0 has bi-directional data binding, which is a big step forward. This means you can bind the UI to a data source (DataTable, object, etc.) and not only display the data, but allow the user to do “in-place” editing that updates the data source when the page is posted back.

The end result is very cool, since it radically reduces the amount of code required for many common data-oriented web pages.

Unfortunately the data binding implementation isn’t very flexible when it comes to objects. The base assumption is that “objects” aren’t intelligent. In fact, the assumption is that you are binding to “data objects” – commonly known as Data Transfer Objects or DTOs. They have properties, but no logic.

In my case I’m working with CSLA .NET 2.0 objects – and they do have logic. Lots of it, validation, authorization and so forth. They are “real” objects in that they are behavior-based, not data-based. And this causes a bit of an issue.

There are two key constraints that are problematic.

First, ASP.NET insists on creating instances of your objects at will – using a default constructor. CSLA .NET follows a factory method model where objects are always created through a factory method, providing for more control, abstraction and flexibility in object design.

Second, when updating data (the user has edited existing data and clicked Update), ASP.NET creates an instance of your object, sets its properties and calls an Update method. CSLA .NET objects are aware of whether they are new or old – whether they contain a primary key value that matches a value in the database or not. This means that the object knows whether to do an INSERT or UPDATE automatically. But when a CSLA .NET object is created out of thin air it obviously thinks it is new – yet in the ASP.NET case the object is actually old, but has no way of knowing that.

The easiest way to overcome the first problem is to make business objects have a public default constructor. Then they play nicely with ASP.NET data binding. The drawback to this is that anyone can then bypass the factory methods and incorrectly create the objects with the New keyword. That is very sad, since it means your object design can’t count on being created the correct way, and a developer consuming the object might use the New keyword rather than the factory method and really mess things up. Yet at present this is how I’m solving issue number one.

I am currently solving issue number two through an overloaded Save method in BusinessBase: Save(forceUpdate) where forceUpdate is a Boolean. Set it to True and the business object forces its IsNew flag to False, thus ensuring that an update operation occurs as desired. This solution works wonderfully for the web scenario, but again opens up the door to abuse in other settings. Yet again a consumer of the object could introduce bugs into their app by calling this overload when it isn’t appropriate.

The only way out of this mess that I can see is to create my own ASP.NET data control that understands how CSLA .NET objects work. I haven’t really researched that yet, so I don’t know how complex it is to write such a control. I did try to subclass the current Object control, but they don’t provide extensibility points like I need, so that doesn’t work. The only answer is probably to subclass the base data control class itself…