When you are setting up a technology stack for new business application, well any kind of application really, one of most basic decision is what presentation tier technology you will use.

You have to ask two basic questions.

• What is demanded richness of user experience?

Must be very responsive? Do you need fancy data manipulation? Will application handle large amount of data? Are those very dynamic? Will application be used just to present data?

• How accessible application must be?

How portable your application really must be? What will be typically users of this application? What client software and hardware platforms are targeted? How often the application will change/update?



This picture nicely summarize those questions, what technology you should use based on your answers to those questions.

To answer to the question in the title. As far as I know typically business application and if I answer to the user experience and accessibility questions I would definitely say, Silverlight technology delivers the best trade off between user experience richfullness and accessibility that typically business application nowadays requires.

Related (picture source):

• http://www.tozon.info/blog/post/2009/09/16/Slides-from-Microsoft-Partner-Meeting-Event.aspx
  

On meta.stackoverflow.com Joel announced a need for countdown application for the coming DevDays, as I am planing to attend one, I have decided to make one. Maybe I will watch my counter at the conference. ;)

It looks like:

Source code: PeterStegnarDevDaysCountdown.zip (198.51 KB)

I have used WPF, .NET 3.5. The speciality of this solution is custom Stackoverflow digits. :)

Short manual:
-you can find exe in "PeterStegnarDevDaysCountdown\WPF_StackoverflowCountDown\bin\Debug"
-start the app with the following parameters, for example: 0900 "DevDays begins in %s"
-just hit an "Esc" key to exit

Core functionalitiy is, of course, countdown:

            if (second != 0)
            {
                second--;
            }
            else
            {
                second = 59;
                if (minute != 0)
                {
                    minute--;
                }
                else
                {
                    minute = 59;
                    if (hour != 0)
                    {
                        hour--;
                    }
                    else
                    {
                        throw new ArgumentNullException("No valid time entry!");
                    }
                }
            }

What do you think?

Today I have compiled a nice podcast MP3 CD with Stack Overflow podcasts from episode 38 to 57. Yeah I know is strange selection, but you have to start somewhere. :)

NerdCD is meant to be regular geek podcasts compilation. Which will contain mainly the following podcast sources:

• http://blog.stackoverflow.com/category/podcasts/
• http://www.dotnetrocks.com/archives.aspx
• http://www.hanselminutes.com/
  

Why NerdCD, anyway?

Well it is primary meant to be record to the CD (size of NerdCD is just under 700 MB) and to be listened in the car. Of course you can upload it on your favourite music player (iPod, mobile phone, you name it).

Where can I get I?

It will be distributable in a torrent form.

NerdCD1 torrent: NerdCD1.txt (12.97 KB) (Caution! Rename txt to torrent file extension - torrent extension is blocked on my server, sorry)

Needless to say, seed it! :)

I would like to point out the difference between (local) and localhost. Those special "addresses" are often used in connection strings.

There are common misconception that, those address are the same. This is not the case.

"... it depends on the provider you're using to connect. If you're using the SQL Server Native Client or the .NET Data Provider for .NET 2.0 the behavior is the same regardless of which name you use (localhost/(local)/or "."). These providers will first try to connect using Shared Memory, then try to connect using TCP/IP and then finally Named Pipes."

It is not advisable to use (local) for other providers, because of the ambiguity (you have 3 different ways to access the SQL server). It is better to explicitly define the connection type (typically TCP/IP), with localhost.

More info:
http://msdn.microsoft.com/en-us/library/ms187662.aspx
http://msdn.microsoft.com/en-us/library/ms191260.aspx
http://msdn.microsoft.com/en-us/library/ms189307.aspx

Sometimes you need a control over browser window behaviour, i.e. open a new one and close it, eventually.

This is really simple. All you need to write is one liner code.

To open an window:

window.open ("http://www.google.com","window"); 

Then you can close it by:

window.close();

In ASP.NET you have variety of ways to achieve browser window close. One example:

closeButton.Attributes.Add("onclick", "window.close();")

By this, close functionality is dynamic added to the control event.

Important: you can close a browser window with code which was open by the code.

However, this open/close window java script technique is more or less obsolete. If you need to display a special "window" to the user, you should use modal windows. ASP.NET AJAX have a nice control, called "ModalPopup".

How to get the file extension from string file name?

Well brute force approach would be something like that:

string fileExtension = args.FileName.Split('.').GetValue(args.FileName.Split('.').Length - 1).ToString();

Pretty ugly, in spite of one liner code.

Well it turns out that the framework has support for this functionality:

string fileExtension = System.IO.Path.GetExtension(fileName);

Much better, right?

It is good to remember that .NET Framework contain a lot of functionality that you would not think about at first place. That's why is good to check every time is something smells that it could be in .NET Framework. You may find it.

Roy Osherove is giving an hands-on TDD Masterclass in the UK, September 21-25. Roy is author of "The Art of Unit Testing" (http://www.artofunittesting.com/), a leading tdd & unit testing book; he maintains a blog at http://iserializable.com (which amoung other things has critiqued tests written by Microsoft for asp.net MVC - check out the testreviews category) and has recently been on the Scott Hanselman podcast (http://bit.ly/psgYO) where he educated Scott on best practices in Unit Testing techniques. For a further insight into Roy's style, be sure to also check out Roy's talk at the recent Norwegian Developer's Conference (http://bit.ly/NuJVa). 

Full Details here: http://bbits.co.uk/tddmasterclass

bbits are holding a raffle for a free ticket for the event. To be eligible to win the ticket (worth £2395!) you MUST paste this text, including all links, into your blog and email Ian@bbits.co.uk with the url to the blog entry.  The draw will be made on September 1st and the winner informed by email and on bbits.co.uk/blog

A jQuery library quickly emerging really popular - and for a reason. I think it is one of the best JavaScript frameworks. You can do fancy stuff really fast and clean.

You can start a Getting Started with jQuery. On the jQuery homepage you can find a lot of nice tutorials. If you have not try jQuery, please do. You will be amazed.

Bassically what jQuery brings to web delopement is that it separates HTML and behaviour. Similarly what CSS brought: separation of presentation and HTML.

There are a great tool named Firebug, which really helps with web development. This tool surely demand a separate post. You can inspect a web page, play with CSS on the fly, debug, use a console ... Here it comes a jQuery. You can write a jQuery instruction right into the console, and it will be applied on the fly. Amazing. All you have to do is to "jQuerify" a web page.

Another great thing to know when you work with jQuery is what the selector will actually select. You can try a SelectorGadget tool which shows the most appropriate selector for the selected element(s). This tool is so great also because all you have to do to run it, just click a "link" when you are on the desired page to be check. Great!

More on Firebug and jQuery in the great video:

• http://polymorphicpodcast.com/podcast/video/firebug-and-jquery/

I have implemented a very simple validation site. You just put an XML and XSD to it and it tells you if your XML document is valid. Simple.

Just vist XML Validation site and try your XML against XSD. Please notice that it is version 0.01 so I presume you know what that means. :)

When and if it will be updated is depended on the planet polarization.


Related:
http://blog.stegnar.com/2009/06/03/SimpleXMLValidationWithNET35.aspx

A very nice thinking came by me from Rockford Lhotka. It is about future of OS. I quite agree with him. Soon we will have just thin client and everything will be in cloud.

http://www.lhotka.net/weblog/OSEvolution.aspx

Just think how many "cloud" things are you already using? A lot. Today is totally possible to have installed just a browser in you machine, and you can do (almost) everything.