I made my first attempt at TDD last week and I definitely like the results. I feel like writing a test first lead me to a much more structured way to writing my code. I felt more in control of where I was going since I already knew what my code would ultimately need to do. Also, having a list of build errors (because of methods being called that don't exist) kept me focused on what I needed to be doing next. I think I still have a lot to learn about this, but I'm happy about my experience so far.

One thing I need to work on is code coverage, but I still have that nagging feeling that spending too much time writing test cases is slowing me down.

Labels: methodologies

I was about to post about how upset I was that the March CTP of Orcas was only available as an over 4GB! Virtual PC image. Then, when searching for a link for this blog post, I found "Orcas" Related CTP Downloads, which has a link for a self-extracting installation to use instead of an image. Huzzah!

Labels: betas

I just received the copy of Windows Developer Power Tools O'Reilly sent me as thanks for my participation on Windows Developer Tools Day two weeks ago. It's a massive book, but seems to be organized so well that it will be easy to read a chapter or two each evening.

In fact, after seeing Jim Holmes' post about the WinDevPowerTools Rollout, I went there and set up my own profile. As tools are added to the site, and as I'm able to check out more tools that I read about on the book, I'll update my profile there.



A lot of the tools that I use regularly either haven't been added to the list or aren't covered by the book. I'm not sure about what's covered by the book yet because I haven't had any time to dig into it yet. I would love it if I could add tools that I use that might not have been covered by the book.

Labels: tools

While searching for the VS 2005 CMD Prompt Here shell extension I stumbled upon some other tools that I really like. First of all, the Clean Sources application does exactly the same thing as a command line application that I whipped up two days ago, except it provides better feedback and is integrated into the explorer shell.

But the best find was by Omar Shahine, the same author of Clean Sources - Clipboard To Image. This application takes care of the manual steps I constantly find myself doing when I take screenshots of application or diagrams, and it even defaults to the PNG format! (yay)

Now I just have to integrate it into SlickRun and move on to being more productive.

** Note:
After playing with Clipboard to Image for a bit, I noticed that if you try to overwrite an existing image, the overwrite never actually happens. So you just have to create a new image each time.

Labels: tools

You would think that calculating the age of a person based on their date of birth would be simple, but it's more tricky than that. Like most problems in programming, things are never what they seem at first glance.

The .NET framework has some greate objects for working with dates and time - System.DateTime and System.TimeSpan, and it's trivial to do a calculation like the following.

public int CalculateAge(DateTime birthDate)
{
return DateTime.Now.Year - birthDate.Year;
}

Our return value has the correct calculation of the difference in years between the current date and the birth date, but that isn't what a typical person considers an age. The following test cases will show that this function isn't correct.

[TestMethod]
public void TestAgeCalculation()
{
DateTime dob = DateTime.Now.AddYears(-1);

// born a year ago yesterday
dob = DateTime.Now.AddDays(-1);
Assert.AreEqual(CalculateAge(dob), 1);

// born a year ago today
dob = DateTime.Now.AddDays(1);
Assert.AreEqual(CalculateAge(dob), 1);

// born a year ago tomorrow
dob = DateTime.Now.AddDays(1);
Assert.AreEqual(CalculateAge(dob), 0);
}

The third test case fails because age doesn't automatically equal the difference in years. Another solution that comes quickly to mind is to get a TimeSpan which is the difference between now and the date of birth, but there's no method that converts a TimeSpan to the number of years. What you can get from a TimeSpan is the number of days, which you can then divide to get years.

public int CalculateAge(DateTime birthDate)
{
TimeSpan ageTime =
DateTime.Now.Subtract(birthDate);
return Convert.ToInt32(Math.Floor(
ageTime.Days / 365.25));
}

This fails too because we consider ourselves to be a year older on our birth day, even though we're actually not a year older until the day after our birthday. Also, I don't really like the division by 365.25 because it's not entirely accurate. Of course, that's all ignoring the time of birth in the equation.

Here is what I finally came up with to accurately calculate an age from date of birth.

public int CalculateAge(DateTime dob)
{
int years = DateTime.Now.Year - dob.Year;
if (dob.AddYears(years) > DateTime.Now)
years--;
return years;
}

Definitely not all that complicated, but more tricky than I imagined it would be when I started to tackle the solution. This is one of those things that all programmers run into at least a handful of times during their career and, I'd hope, take some time to make sure their code is accurate, but it's easy to just throw code out there that works 98% of the time.

Labels: c#

I was walking down a empty hall, not sure where I was. Ah, there's the room I was looking for. As I walked through the door, the people inside turned around and looked at me. Some had clothes with penguins on them, or carried devices with logos of partially eaten fruit. "Where you from, cuz?" the one up front said. Oh no, I'm dead now!

Okay, so maybe that's what I imagined it might be like walking into a session focused on Python. I was definitely outside of my Microsoft comfort zone. But that's what CodeMash is supposed to be about, so I figured I'd go out of my way to see a presentation on something almost totally unknown. It turned out to be nothing like my overactive imagination, and I don't think I stood out at all. I'm not sure why I expected anything different, really.

I was at Mark Ramm's presentation on SQL Alchemy. Honestly, I wasn't following all of the details and I'm not clear on what I took away from it. At the very least I gained a basic understand, exposure or awareness of something that I wouldn't normally see. It was definitely interesting, but the Q & A was totally over my head so I ducked out early.

There are a few things I've noticed about CodeMash so far. As the conference has progressed, I've noticed people being a lot more comfortable asking questions or giving comments without being prompted. So far, the sessions I've been in where the audience contributed have been the best experiences.

Also, I never imagined I'd be live blogging, but today I found that I had a lot to say. I still don't like the term and wouldn't really admit to doing it.

Oh yeah, and I sat near a guy who totally looked like Don Knotts.

Labels: codemash

Today's sessions that I plan on attending definitely focus on data access, which actually has me excited after the ridiculous models at my last job.

I just got out of Scott Guthrie's keynote on LINQ. LINQ definitely has me excited, and I need to play with the release from last year.

Right now I'm in Dave Donaldson's session on NHibernate. Code with no more stored procedures? Excellent! I'll follow up later with my impressions.

Impressions:
Dave has written an interesting framework called NHibernateRepository that I might look into using. Its not integrated into the NHibernate project, but Dave said that he's going to eventually look into getting it incorporated into a contrib project.

I was suspicious of what the performance would be with an O/R mapper, but since NHibernate uses parametrized queries, its virtually no different from stored procedures in that respect. From Dave's demo I got the impression that if you need to do tricky things, the way to go about it is using a syntax called HQL, which looks just like hard coded queries, and weren't we supposed to get away from that?

Differences between NHibernate and LINQ were also on my mind. LINQ has a nice visualizer that shows the actual query when you're debugging, which is a lot nicer than having to use the profiler or read a log file. It occurred to me when NHibernate's insert/update/delete features were being demonstrated that I haven't seen any examples of updating data with LINQ. Is LINQ supposed to be used solely to query data, and not modify it?

You have to write a lot of configuration and code by hand with NHibernate .... unless you use a code generator. Dave demonstrated a CodeSmith template that would (have if it hadn't crashed) create entity classes and config from your database. But the code still wasn't pleasing to look at. I wondered if, like Dave's NHibernateRepository library, if anyone has adapted the Data Access Application Block to work with NHibernate, or another O/R Mapper for that matter.

Another, maybe totally unrelated, thought was "where is the c# in stored procedures?" C# embedded in stored procedures was a feature that was highly touted in .NET 2.0, but I have yet to see anyone use it other than code in MSDN documentation. Is this feature really something people want to use? Don't we want to stay away from business logic in stored procedures? Yeah.

I'm in Mark Ramm's session on O/R Mapping with SQL Alchemy right now, which is definitely outside of my comfort zone. This is what CodeMash is supposed to be all about, so we'll see how I like it.

Labels: codemash

I made to CodeMash with about 10 minutes to register before the morning keynote. I'm really glad I made it to the keynote, which was about domain specific languages. Neal Ford did a really good job and I can't wait to go back through his presentation and compare it to my notes about ways I could incorporate DSL into some various ideas I have. I'm not ready to share those ideas yet, but when I feel like they're not totally silly I'll be posting them here.

Other sessions I attended today were ...

• Smart Clients - more like an introduction and didn't see anything I didn't already know.
• Ruby on Rails - This was a pretty cool session on Active Record and talking about how Rails works. My only complaint is that I should have sat closer because I couldn't read the text on the code examples.
• TDD - a session about benefits from TDD beyond the main idea of units tests - very good.
• An excellent keynote by Bruce Eckel that ... well ... I'm not sure what the focus was, but it was very entertaining and sparked some interesting thoughts.

I'm not sure what to expect tomorrow, but if its anything like today I'm going to be rocked. I know it starts off with Scott Guthrie doing a talk on LINQ, which I'm stoked for.

Labels: codemash

I always feel a little bit guilty when I read Microsoft newsletters through gmail.

I think Google knows this, and is trying to help ...

Labels: humor

Some of the things I read in R. Aaron Zupancic's blog post New Operator in C# 2.0: ?? caught me off guard. I swear I'd read through several articles listing changes and additions in .NET 2.0 and C# 2.0, including MSDN, but never ran across the ?? operator. I even checked the C# Operators documentation and didn't see ?? Operator until the second pass, because it's grouped in the assignment category. I expected it to be grouped in the conditional category with ?:, but now I'm wondering why ?: isn't considered an assignment operator?

While the null coalescing operator is cool and looks nice in code, I'm not sure how much I'll use it. Most of my code where I'm checking whether a variable is null throws an exception or takes some other action instead of using another value in place of the null variable.

The most interesting thing that I noticed was the following comment from Owen Blacker:

It's even cooler than that. The null coalescing operator does type forcing, too.

Imaging you have this:

public int? GetUserID() { ... }

int userID = GetUserID() ?? -1;

The ?? operator not only provides an alternative value if GetUserID returns null, but it also does type conversion, from the int? result of GetUserID to a non-nullable Int32, if it returns a non-null result.

I was really thrown off by the int? part of the example code in the comment above. I eventually found that it's the same thing as NullableType. That's really nice syntax to replace using a nullable value type. Before I knew what it was, I immediately assumed that it was something like a nullable type. The question mark following the value type suggests that you're not sure that the returned value will be integer or not. I will definitely get some mileage out of this information. Finally, a way to represent a value from a SQL bit column in code.

I'm not sure why I forgot about Nullable Types. I do recall reading about them in the feature list for a .NET 2.0 beta, but I don't remember seeing anything about them in any "what's new" articles. Maybe I just missed it.

Back to the operator, I think the next example reads a lot cleaner than the following one which uses the NullableType's GetValueOrDefault() method. Of course, its probably better to use that method so you aren't hard coding a value type's default value in code (not that it would change).

Using the ?? operator:

int? x = null;
int y = x ?? 0;

Using the GetValueOrDefault() method:

int? x = null;
int y = x.GetValueOrDefault();

It's interesting that the null coaelscing operator post is making rounds now, almost exactly a year after it's original posting.

Labels: c#

Yesterday I posted about input devices, and mentioned that I couldn't configure the thumb button of my Microsoft USB Comfort Optical Mouse 3000 to enter the Alt+Tab keystroke. So what did I set as the functionality of the thumb button? I just had it configured to the default Back button functionality, which I found myself never using, and left it at that. Then I found a utility that lended itself very well to being mapped to the thumb button.

Clipboard Recorder is a utility that stores the last 100 snippets of text that have been copied to the clipboard. Among it's several interfaces, there is a pop-up menu that can be activated with the keystroke Ctrl+Alt+V. I mapped this keystroke to my mouse's thumb button and, viola! My favorite mouse configuration ever!



I don't know how I lived without a clipboard history up to now. As a software developer, it is indispensable. Copying and pasting sections of code is something done every day, and it's very nice to be able to copy code knowing that you'll need it later, but not worrying about overwriting it in the clipboard, and maybe having to store it in a temporary text file. Also, our defect management software at work leaves a lot to be desired, and I find myself copying and pasting the same 3-4 pieces of information into several places, including VSS.

I love Clipboard Recorder and that's why I registered it on "Support Your Favorite Small Software Vendor Day" last month.

Some other utilities that I use daily:

• EditPlus
• Trillian
• Windows Grep
• UltraMon
• SlickRun
• BareTail
  

And some utilites that I use every now and then:

• Beyond Compare
  
• AutoHotKey
• BitPim
• CDex
  
• The Regulator
  

Also, I have del.icio.us utilities links to tools that I want to check out some day.

Update:
I'm counting this as my official "Tools Day" blog post, in support of Jim Holmes and James Avery's new book "Windows Developer Power Tools".

Labels: tools