The previous edition of this book, 4th edition, remained at arm's length at all times at work and rescued me repeatedly from various day-to-day JavaScript challenges. It has become tattered from rigorous use. I always loved how the book was organized, with the first half as a walk through the entire gamut of JavaScript's workings -- tutorials, walk-thrus, code samples, cross-browser issues, and practical solutions -- and the second half of the book as a complete JavaScript language and DOM reference. That already very useful format has actually been improved upon. David has combined the DOM API reference and client-side JavaScript reference into a single alphabetized section. Now that I think about it, I did find myself flipping back and forth a lot in the previous edition, so this is a welcome improvement. Each object, property, and method contains a helpful "availability" of that item. This may be the standards spec it came from [DOM Level 2 HTML, ECMAScript v1], the JavaScript version in which it emerged [JavaScript 1.0], or a list of browser versions, if it is a proprietary feature. This is critical info to have at-a-glance - could perhaps save you 2 days of work implementing a non-standard, IE-specific JavaScript feature, when you could have been coding the standards-compliant equivalent. David has removed a lot of the deprecated, not-widely-adopted DOM interfaces that no longer apply to modern browsers. David has also moved focus away from some of the more oddball DOM interfaces that have been replaced by more sensible JavaScript objects that implement those interfaces, for example, window.getComputedStyle() rather than AbstractView.getComputedStyle(). In other words, David has removed all of the "stuff that still exists, but you no longer need to worry about". This makes for a more focused, less cluttered, "on topic", useful tome. I don't need to know about the 10 different methods that browser manufacturers fought over 7 years ago. Tell me what I need to know NOW to write practical, functioning, modern, cross-browser JavaScript. That's exactly what Mr. Flanagan has accomplished.
What else is new in the 5th edition?
1. Nested functions and closures.
2. A dedicated "Classes, Constructors, and Prototypes" chapter, with much more coverage on object-oriented programming in JavaScript.
3. A new chapter on Modules and Namespaces.
4. New chapter on scripting Java with JavaScript.
5. Coverage of the legacy (Level 0) DOM has been combined with the W3C standard DOM. More consolidation. Less flipping back and forth.
6. Cookies and Client-Side Persistence. Updated coverage on cookies, and brand new coverage of other client-side persistence techniques, like IE userData persistence, and Flash Shared Object Persistence.
7. AJAX - Coverage of scripted HTTP calls using the now famous XMLHttpRequest object.
8. XML - Demonstrates how to create, load, transform, query, serialize, and extract info from XML docs.
9. Client-Side Graphics - JavaScript's graphics capabilities. The cutting edge <canvas> tag, SVG, VML, and communicating with the Flash plug-in.
10. Scripting Java Apps and Flash Movies - Another brand new chapter.
So, is the 5th edition worth the purchase? Absolutely. This book is a must-have for any web development library. I turn to it repeatedly. Here's an example.
Last week, I overheard a developer on my team proclaim to someone, "We can't do that. JavaScript can't control stuff in another frame." They went and informed my boss how monumental their task was becoming as they proposed a hacky, inelegant server-side workaround.
I managed to grab the one developer and said, "JavaScript certainly can talk across frames."
"Really?!", he asked, astonished. I opened "The Definitive Guide" to the part on cross-frame scripting and bookmarked it for them.
"Oh, wow! GREAT!", he exclaimed, "That completely solves our problem. Totally cool!" and zipped away book in hand. Hours later, they had it worked out, rather than days with the server-side solution.
I've seen some one-star, complaint-type reviews posted that this isn't a beginner book. Exactly right, but I'm confused as to how a quality rating [of 1 to 5 stars] equates, in any way, to skill level of the book, or its ability to meet someone's self-conceived personal notions of what the book is supposed to contain. There are some overview-type chapters that go over syntax, operators, scope, expressions, and the usual array of language basics, but these reviewers are correct in that this book is not a beginner's tutorial on JavaScript. It is a meat and potatoes, soup to nuts definitive guide and reference on all of the important and practical aspects of JavaScript programming. It is not a cookbook of cute-but-useless cut-n-paste recipes [although there are plenty of USEFUL code examples]. It is not the quick-and-dirty example of how to slap the hottest AJAX library into your site to attempt to make it behave like a Windows app. The chapter on AJAX shows you how to use the XML HTTP object directly, wrapped up in some nice reusable routines, so you can WRITE YOUR OWN AJAX-based features [which I prefer over using someone else's complicated, obfuscated framework].
Great job, again, David! If you develop websites in any capacity, you need this book. It should be on every developer's shelf.
