*Words of Wisdom From The Elder

TechEd 2010 was in New Orleans last week and I had the pleasure of doing a full day pre-conf session at TechEd.  Pre-confs are longer sessions where attendees can get into more details.  This year I did “.NET From Scratch” which was a one day session to introduce developers to the .NET platform. 

This seminar is for anyone who is starting at ground zero with .NET and wants a deep dive into the platform starting from scratch. It is designed for developers experienced in at least one other language, and starts with the basics of . NET and covers Microsoft Visual Studio, writing code in C#, and how to build applications in various technologies of the platform such as Windows, Web, Microsoft Silverlight, and Windows Mobile. If you are new to writing applications on Microsoft .NET, what better way to start your Tech·Ed experience?

As promised to the attendees, the slide decks and demos can be downloaded from the following URL:

http://keithelder.net/presentations/NETFromScratch/NETFromScratch.zip

Remember when learning a new platform as large as .NET the main thing to focus on are your immediate needs.  That may be a language and a framework and possibly web programming.  It is impossible to learn or know everything about a platform as large as .NET but knowing what is possible is half of the battle.  As engineers if we know it is possible it is just a matter of research to figure out how to make it happen. 

A big thank you to those that attended the session and I am truly sorry about how cold it was in the room.  If I’d known in advance I’d brought some firewood and blankets.  Enjoy.

 
http://deepfriedbytes.com/podcast/episode-50-behind-the-scenes-of-the-net-languages-with-luca-bolognese/

Ever wonder how your favorite features from C#, VB.NET and F# get selected, implemented and finally reach your fingers? We did too and we found a great person to get the behind the scenes story from Building 41 in Redmond. In this episode, we sat down with Luca Bolognese, former Group Program Manager at Microsoft, to discuss how the languages team decides which features to include in the .NET languages.  We learn also what is coming in NET 4.  Join us for this episode as we uncover some hints on what may be coming in the .NET future, something you don’t want to miss!

I’ve done this twice now and I know if I’ve done it others probably have as well.  Here’s the short story and the fix.

Let’s say you create a new project to play around with a WCF Data Service to create some OData.  You add an entity framework model from an existing database and then add a WCF Data Service.  Things are going along nicely.  To get something up and running quickly you modify the WCF Data Service to look like the following.  All looks good.

   1: namespace WcfService2

   2: {

   3:     public class WcfDataService1 : DataService<NutshellEntities>

   4:     {

   5:         // This method is called only once to initialize service-wide policies.

   6:         public static void InitializeService(DataServiceConfiguration config)

   7:         {

   8:             // TODO: set rules to indicate which entity sets and service operations are visible, updatable, etc.

   9:             // Examples:

  10:             // config.SetEntitySetAccessRule("MyEntityset", EntitySetRights.AllRead);

  11:             // config.SetServiceOperationAccessRule("MyServiceOperation", ServiceOperationRights.All);

  12:             config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2;

  13:             config.SetEntitySetAccessRule("Customer", EntitySetRights.All);

  14:         }

  15:     }

  16: }

Then you build your solution thinking you are about to strike gold when all of a sudden you are presented with this nasty unhelpful error:

Request Error

The server encountered an error processing the request. See server logs for more details.

The problem lies in line 13.  See the string?  Yeah, that’s a spot where we as humans have to type something and let’s face it, we make mistakes.  I’ve done this several times already.  To fix this, look at your model and make sure you have the correct name.  Here is my playground model:

Yep, it was suppose to be “Customers” instead of “Customer”. Change line 13 to “Customers” and all is well.

I started writing this as a general recap of PDC for team members but the more I thought about what was announced at PDC, the longer the email got.  Ultimately I decided to put it out so you dear reader could also gain some insight from things announced at PDC. 

For starters listen to the podcast we recorded with Scott Guthrie or “The Gu”, or “His Guness”, or “ScottGu” about Silverlight 4 announcements among other things while at PDC. 

The big stories out of PDC that I think everyone should take note of are Silverlight 4, Entity Framework 4 and Windows Mobile. Wait Windows Mobile 7? Yes.  Wait… I didn’t hear anything about Windows Mobile 7? Well I didn’t either and that is why this post is called “read between the lines”.  Call it speculation or whatever, but I think I can bring you up to speed on what is about to happen (and no I have no official behind the scenes information, I’m just a guy with a brain).  Before we get to Windows Mobile 7, let’s start with Silverlight.

Silverlight

Silverlight 4 had tons of announcements including:

• Camera and microphone support
• Trusted out of browser support.  This means one can access COM (for example, an application could access Outlook APIs)
• Lots of line of business app controls
• Added support for drag and drop
• WCF RIA Services (this is basically what I’m calling the new CSLA, if you listen to the podcast you’ll find out that Rocky worked with the team closely on RIA Services)
• Print natively
• More…

Tim has a great recap of all the Silverlight announcements here with links to videos:

http://timheuer.com/blog/archive/2009/11/22/pdc-silverlight-resources-link-dump-learn-silverlight.aspx

Now what does this all mean? It means the line is blurring between client and server applications. It also means we are coming back full circle to “Smart Clients” (which were hot in 2005/2006 but were forgotten due to the Web 2.0 hype.  The only difference is this new breed of application (Silver Clients?) can run directly from a web site, or on a client’s machine.  It also means that Silverlight is going to finally fulfill the vision we heard about a long long time ago that was called WPF/e (WPF Everywhere).  A lot of people have forgotten this but we are seeing it take full shape now.  For businesses that are writing applications internally, I think we are going to start seeing a huge shift away from writing Asp.Net/MVC apps and a move towards the rich model with Silverlight.  I mean seriously, why wouldn’t you? If you get cross platform compatibility, rich data binding, write once and work in any browser, why would developers that are trying to build internal business applications continue to kill themselves writing JavaScript, fighting CSS and browser compatibility?  I can’t think of a reason either.  In my opinion this is just a waste of time (and always has been).  There is something extremely powerful putting a variable in memory and having it be there when you need it without having to worry about sessions, state, etc.  Yes we are FINALLY getting back to the client programming model, just coming at it a different way. 

Entity Framework

Let’s talk about Entity Framework 4.0 for a moment.  This is another big piece of news.  It is big because as .Net developers we will finally have one true way to access data that fits the multitude of ways we have to work.  Here’s a recap of announcements (not a complete list, watch the videos from PDC):

• POCO – supports plain old clr objects
• EDM designer enhancements
• Better stored proc support
• Model first (then gen database model)

Doug Purdy (who we also interviewed for Deep Fried Bytes while at PDC) has a list of the sessions that cover the Entity Framework 4.0.  Just start at the top and work your way down as far as you can.  At least watch the first video as it shows off all the features of EF.

http://www.douglaspurdy.com/2009/11/22/pdc-2009-data-and-modeling-talks-2/

With the number of features that were announced in EF4 I think we are on the verge of seeing the demise of NHibernate usage by developers in the .Net stack.  For those that have used NHibernate in the past, it is worth another look at the Entity Framework to be released in .Net 4.0.  About the only thing EF4 doesn’t do that NHibernate does do is built-in caching (which hey, there’s this caching thing that AppFabric does, hmm, wonder if they’ll use that? Why not! 🙂 ).  But the big thing to note between EF4 and NHibernate is we are starting to see where this whole modeling thing with OSLO is going (edm files are m fles and so on).  And of course there is the bigger picture of reusing this model in report services, BI and other areas (although we haven’t *seen* that really working yet, it is coming though see next sentence).  As EF4 makes it way into other products throughout the Microsoft ecosystem it is going to be extremely hard to avoid the Entity Framework.  Read between the lines, the writing is on the wall, LEARN THE ENTITY FRAMEWORK.

Just a side bar here because I know someone is going to ask me this at a later time.  Will the Entity Framework kill NHibernate? Answer: Nope I’m not saying that. 

Out of band developers that seem to have a knack for yelling the loudest will continue to use NHibernate but a much larger ecosystem will leverage the out of the box Entity Framework in .Net 4.0.  Think back for just a bit.  History is about to repeat itself all over again.  Remember when we got MSTest and or MSBuild?  Same thing is happening again. There is now an out of the box product for standardizing data access.  Are their alternatives? Sure.  Just as MSTest didn’t kill NUnit or MBUnit and MSBUILD didn’t kill NAnt, EF4 will not kill NHibernate.  However, if you look at the number of developers using MSBuild or MSTest it is high. Extremely high.  Why is that? Answer: pain, ease of use, integration, documentation.  MSTest is not the best testing framework out there (this is a proven fact), but it is good enough for 90% plus test cases.  Entity Framework 4.0 is going to put an ORM in the hands of developers.  And you know what, it doesn’t suck either. 

Windows Mobile 7

And now onto Windows Mobile 7. 

Is this WinMo 7 above?  I honestly don’t know, I found these screen shots on http://windowsphonemix.com/ web site.  BTW, notice that URL?  Mix? Yes Mix.  Mix is the first of the three major conferences Microsoft puts on each year.  The very last slide at PDC during the last keynote said, “Come to Mix 2010 for Windows Mobile 7 futures”.  A lot of people missed this because they were tuned out from the SharePoint demos and already packing to leave.  But there it was on the big screens.  Thus we know Mix is when we’ll see Windows Mobile 7.  Again, listen to the podcast to get some other insight. 

Here’s a quote:  “Three screens and the cloud”

We heard this over and over at PDC.  Let’s read between the lines a bit shall we?

I have three screens:  Windows Desktop, Web, Mobile.  Ok, if I want to write an app that will run on all three what do I as a developer have to do today?  Let’s see, well, we could write a ClickOnce deployed Smart Client for the Desktop that uses WPF.  For the web, well, we would have to switch gears completely and rewrite our app in Asp.Net or Asp.Net MVC to get that screen.  For mobile, even tougher, we have to rewrite the app again to get the mobile version.  Let’s think about this differently again.  Think about it, how many technologies would a developer have to know in order to an application for these three different screens;  WPF, JavaScript, HTML, and CSS will be used just to name a few.

Now, let’s switch gears.  What if I used Silverlight 4 to write my app?  Well, it could work in the browser no doubt.  Hmmm, it could also work on the Desktop using the out of browser experience with elevated permissions.  What about mobile? 

“Wait, didn’t you just say Keith that at Mix we’ll get to see Windows Mobile 7?”

Yes! 

“And hasn’t there already been talk of using Silverlight for mobile?”

Yes!

“Aha! Three screens with Silverlight, I get it!”

That’s right my friendly .Net developers the writing is on the wall. The vision of WPF/e (WPF Everywhere) is about to come true.  We’ve waited for years but it is just around the corner as I predicted would happen years ago.

http://www.keithelder.net/blog/archive/2007/01/12/Microsofts-Response-To-The-iPhone-Is-Right-Around-The-Corner.aspx 

(ok, so it wasn’t right around the corner but 3+ years later)

Moral of the story?

LEARN SILVERLIGHT so you can make millions of dollars building Mobile applications just like the iPhone devs.  There, I just made you rich by putting this puzzle together for you, please send me 20% of all profits.

You are welcome.

Yesterday evening at work a team member and I were pair programming.  We had a disagreement about how to code a few lines.  The question was around whether to use the ?? operator or to use an if statement using String.IsNullOrEmpty.  We settled it like most developers do and that is with a benchmark.  Here’s the fun we had.

To give you an idea as to what we were doing here’s some context.  We had a function that took an object.  We wanted to add extra context data to the object, but only if the object didn’t have it set.  In other words, the data may have already been set somewhere else in the application and we didn’t want to override what was already set.  There were two ways to do this and since I was typing I started typing the following.

   1: private void AddContextData(LogEntry entry)

   2: {

   3:     entry.Url = entry.Url ?? HttpContext.Current.Request.Url.ToString();

   4:     entry.UserIpAddress = entry.UserIpAddress ?? HttpContext.Current.Request.UserHostAddress;

   5:     entry.UserName = entry.UserName ?? HttpContext.Current.User.Identity.Name;

   6: }

My pairing partner started in on me immediately.  He was thinking it should be written like this.

   1: private void AddContextData(LogEntry entry)

   2: {

   3:     if (String.IsNullOrEmpty(entry.Url)) entry.Url = Context.Current.Request.Url.ToString();

   4:     if (String.IsNullOrEmpty(entry.UserIpAddress)) entry.UserIpAddress = HttpContext.Current.Request.UserHostAddress;

   5:     if (String.IsNullOrEmpty(entry.UserName)) = entry.UserName = HttpContext.Current.User.Identity.Name;

   6: }

The ?? for those that aren’t familiar with it is called the “null coalescing” operator. Scott Gu wrote about it late 2007 if you want some additional information and samples.  It is a fun little operator and can save you a lot of typing in more places than you think.  Most developers though don’t think to use it and instead code the long handed version doing a check using a if block. 

In the end we decided to settle our disagreement and go with the one that was the fastest.  Thus we whipped up a quick benchmark to test one vs. the other.  Here’s the benchmark code for both samples.

?? Operator Benchmark Code

   1: string x = "foo bar";

   2: Stopwatch watch = new Stopwatch();

   3: long ticks = watch.Time(() => x = x ?? "bar foo", 100000);

   4: textBox1.Text += "??: " + ticks.ToString() + Environment.NewLine;

Note: If you copy the above code, it will not work on your machine unless you have a Time() extension method as part of your arsenal. 

if { } Benchmark Code

   1: string x = "foo bar";

   2: Stopwatch watch = new Stopwatch();

   3: long ticks = watch.Time(() =>

   4:                             {

   5:                                 if (String.IsNullOrEmpty(x))

   6:                                 {

   7:                                     x = "bar";

   8:                                 }

   9:                             }

  10:                 , 100000);

  11: textBox1.Text += "if: " + ticks.ToString() + Environment.NewLine;

The Results

The results were not all that exciting. Really it only proved there was wasn’t any difference in speed, if anything giving a very very slight edge to the ?? operator.  At any rate it was a fun side bar to end the evening.  Happy null coalescing!