Just wanted to remind everyone about the upcoming She’s Geeky Event in Mountain View CA Jan 30 – 31st. I already registered and got my flight booked so that I can be there. I hear from people who went last year and to the most recent one that the experience has been really good. So go check them out and get registered if you want to go.

Cheers
Desi

A recent posting to a technical mailing list I’m on asked how to pass a parameter to a button click-event handler. The programmer wanted to do the equivalent of this:

<asp:button ID="btnSubmit" runat="server" OnClick="Btn_Onclick(PARAM)" />

But, she knew this didn’t work, because the default signature of event handlers in ASP.NET is this:

void myBtn_OnClick(Object sender, EventArgs e)

So, she was stumped on how to pass some sort of argument to the event handler.

Now, there a certainly some kludges that would work, such as having a hidden form field which contains the ‘parameter’ value, and having the event-handler get the value that way. But surely, there’s a better way? Well, yes, of course there is!

This better way is to use the “CommandArgument” property on the button control. This property is directly accessable in the event handler. The added bonus is that you can write a single even-handler for all of your button clicks, and use the associated “CommandName” property to know which button fired.

So, now, in your aspx page, your button object will be declared thusly:

<asp:Button ID="test" runat="server" CommandArgument="MyVal" CommandName="ThisBtnClick" OnClick="MyBtnHandler" />

Then, in the OnClick handler, you can cast the sender object to the correct type, and get the values of
CommandName & CommandArgument. (You could make this even more generic and handle the OnClick event for different senders, but we’ll leave that for a later post!

void MyBtnHandler(Object sender, EventArgs e)
{
	 Button btn = (Button)sender;
          switch (btn.CommandName)
          {
                case "ThisBtnClick":
                    DoWhatever(btn.CommandArgument.ToString());
                    break;
                case "ThatBtnClick":
                    DoSomethingElse(btn.CommandArgument.ToString());
                    break;
           }
}

You can see that the switch statement uses the CommandName property to determine which button was clicked, and then can use the CommandArgument property passed in by the button click event.

Voila! You’ve “passed a parameter” to a button click-event handler!

[UPDATE] Thanks to Jim for pointing out some confusion in my sample code. I hope that this version is clearer.

**List last updated 04/19/07** (This list just keeps growing)

Ruby has generated such great interest and following since the launch of Rails. Mantra: Do get a book of Ruby before diving into Rails.

Now while researching, I found links here and there but they were all varied depending on your skill level. This (post) is an attempt and probably not the first attempt to group links, books and training sessions available by skill level. Only published books are included at the time of this writing (..most of them I’ve read and own). I have not included books and links that delve more into getting your rails app into production mode other than Capistrano and Mongrel. Such other methods might end up in another post or as an addendum at a later time. The Advanced Level is geared toward Rails.

A must have reference book:
Ruby In A Nutshell – by Yukihiro Matsumuto

BEGINNER LEVEL –

This level assumes that you are familiar with basic HTML, basic networks/servers and familiar with databases but have no prior programming background and entirely new to back end development.

B-L 1. Books/e-Books/Screencasts:

(Ruby)

• Learn to Program
  - by Chris Pine
• Introduction to Ruby
  - by Jim Arlow, Ila Neustadt
• Everyday Scripting with Ruby: For Teams, Testers, and You
  - by Brian Marick

(Rails)

• Build Your Own Ruby on Rails Web Applications (Rails 1.2)
  - by Patrick Lenz (I personally give this book a 5 Star)

B-L 2. Links:

• Ruby-Lang
• Ruby Wiki Book
• Ruby Cheat Sheet v.1 – Cenophobie
• Ruby on Rails
  - with links on How to install Ruby and Rails in a dev environment
• Ruby on Rails Wiki Book
• Rails API
• Rails Cheat Sheet – ILJD

B-L 3. Training/Classes:

• Ruby on Rails Training – Pragmatic Studio
• Ruby on Rails TDD Boot Camp – Obtiva
• RoR: Intro to Intermediate – RubyPal/David Black

INTERMEDIATE LEVEL –

This level assumes that you are very familiar with HTML, CSS, Javascipts, databases and have been doing back-end development with either ASP, Coldfusion, PHP, .NET and Java

I-L 1. Books/e-Books/Screencasts:

(Ruby)

• Ruby for Rails: Ruby Techniques for Rails Developers (5 star)
  - by David Black
• Programming Ruby: The Pragmatic Programmers’ Guide, Second Edition
  - by Dave Thomas, Chad Fowler, Andy Hunt
• The Ruby Way, Second Edition: Solutions and Techniques in Ruby Programming
  - by Hal Fulton

(Rails)

• Agile Web Development with Rails, 2nd Ed. (Rails 1.2)
  - by Dave Thomas, David Hansson, Leon Breedt, Mike Clark, James Duncan Davidson, Justin Gehtland, Andreas Schwarz
• Introduction to Ruby on Rails and Ajax
  - by Jim Arlow, Ila Neustadt
• RailsCast (Podcasts last from between 1 -7 mins so far. Two thumbs up. 5 star)
  by Ryan Bates

I-L 2. Links:

• Start At The Beginning
• Top 12 RoR Tutorials (some outdated)
• Top 30 RoR Tutorials (some outdated)
• Amy Hoy’s Blog
• RubyForge

I-L 3. Training/Classes:

• Ruby on Rails Training – Pragmatic Studio
• Ruby on Rails TDD Boot Camp – Obtiva

ADVANCED LEVEL -

This level assumes that you are breathing and thriving in ruby and running rails applications plus adding Ajax, Subversion, Capistrano and Mongrel into the mix.

A-L 1. Books/e-Books/Screencasts:

• Rails Recipes (5 star)
  - by Chad Fowler
• Rails Cookbook (5 star)
  - by Rob Orsini
• Ajax on Rails
  - by Scott Raymond
• The Money Train (Rails 1.1.6.)
  - by Ben Curtis
• PeepCode ScreenCasts
  - by Geoffrey Grosenbach et al
• Pragmatic Version Control: Using Subversion
  - by Mike Mason
• Mongrel
  - by Angel Dobbs-Sciortino
• Mongrel (Digital Shortcut): Serving, Deploying, and Extending Your Ruby Applications
  - by Matt Pelletier, Zed Shaw
• Bestechvideos for ROR
  - collections by Alexey Kovyrin

A-L 2. Links:

• Capistrano: Automating Application Deployment Manual
• Mongrel at RubyForge
• Rails Migration Cheat Sheet
• The Rails Way < - I love this - Jamis Buck & Michael Koziarski
• Putting REST on Rails
• RESTful Rails Cheat Sheet
• Liquid’s Screencast
• Brians Eng’s Rail Links
• Obie Fernandez’ Blog
• Whys’ RedHanded
• Geoffrey Grosenbach’s Blog
• RubyForge’s Code Snipets
• InfoQ’s Ruby Section
• PluginAWeek

A-L 3. Training/Classes:

• Advanced Rails Training – Pragmatic Studio
• Enterprise Ruby: Bending Railsâ„¢ – Obtiva

There’s quite a few blogs out there that are just THAT awesome but do check out Planet RailsConf’s blogroll for a quick list.

I’d love to hear if you have a link or book to recommend and why you’re recommending it.

I’ve been playing with migrations in the past couple days. Migrations: a way to build and update your database schema within Rails, without using SQL, w/o losing data, and with the ability to fold your schema changes into your application so it’s easy to rollback to an earlier version of a DB or up to a more recent one. Given that ‘how do we change the DB w/o breaking the app’ problems can be painfully real, this is a really amazing tool. As DHH says on the screencast page, “going back to your former treadmill after being exposed to these movies can be exceedingly painful”. Yup. I’d already had a schema up for the project I’m starting, but was inspired to take it down and re-do it using migrations. They’re pretty amazing. Here’s a list of links I found particularly helpful, in case anyone else wants to get started, refresh, or just look at a list of links for fun:

• DHH Screencast — a nice talk that you can rwd & ffwd for practice. Quicktime mov. in browser.
• Great talk with fun colors (not the usual yellow on blue PPT I see at medical conferences) given at Railsconf — this is a PDF, simple things to complex things, includes migrating existing databases, easy to follow, 79 pgs.
• Rails API — helpful for things like change_column, rename_column, etc. Methods not found in the basic tutorials (but that you quickly realize you need!)
• Migrations Cheatsheet — points you in a lot of good directions; mentions “snippets”, which were tantalizing to watch in the screencast.
• Rails Wiki

That’s it for now. More later on my own specifics if anything interesting comes to light.

Q: How do you h/t map your own pluralization word-pairs into rails? (S.G.)
A: You will find the following in environment.rb. You can uncomment the code
that iterates through the inflections and add your own custom rule. (A.O.K)
# Add new inflection rules using the following format
# (all these examples are active by default):
# Inflector.inflections do |inflect|
# inflect.plural /^(ox)$/i, ‘\1en’
# inflect.singular /^(ox)en/i, ‘\1′
# inflect.irregular ‘person’, ‘people’
# inflect.uncountable %w( fish sheep )
# end