Pro Javascript Techniques [ペーパーバック]

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"Pro JavaScript Techniques" is definitely for experienced and advanced scripters. The level of abstraction is high in this treatment of the latest trends of JavaScript. If you are looking for ready-made scripts to solve some specific problem in your site or application, you are looking for a different sort of book.

If you have ever gone to Douglas Crockford's site to learn about advanced concepts in JavaScript, and withdrew dazed and abused by his obtuse examples -- but with a conviction that there was something valuable to learn there -- this book is for you.

The author states, and I agree, that understanding Chapter 2, "Object Oriented JavaScript" is the key to the puzzle. "The phrase object-oriented JavaScript is somewhat redundant, as the JavaScript language is completely object-oriented and is impossible to use otherwise. However, a common shortcoming of most new programmers is to write their code functionally without any context or grouping."

The chapter contains a clear exposition of what the author means by "context or grouping." In fact, his concise but relevant example code to explain the distinction between privileged methods and static methods lit up all sorts of light bulbs in my head...Finally! :-)

Be aware that the author's approach has a particular bias in that it is often directed at the *programmer* coming into Web scripting. The idea is to make the JavaScripting world appear more like the programming languages already known. You learn "how to go about writing a variety of object-oriented code to suit anyone coming from another programming language."

This is a great book -- but not for all.

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As a javascript dabbler, I was looking for a book aimed at someone already familiar with javascript and found this one. Having read a few apress books, I felt pretty confident that the quality of this one would be at least reasonable and I definitely wasn't let down.

The executive overview is that this is an excellent book for those who are already working in javascript and are looking to improve their game. It covers a world of techniques very well. Highly recommended.

Now, the longer review...

This is an excellent book that deftly avoids the pitfalls so many books that claim to be aimed at people familiar with the topic. So many of these types of books try to be accessible they end up giving a lot of basic information mixed in with the advanced information - ultimately becoming a text unsatisfying for people of any level. This book devotes the beginning 15% of pages going over the basics, but it covers a ton of ground by acting more as a refresher course - assuming at least basic familiarity with most of the topics. I think it really did a great job of this, starting in Chapter 1 with a broad overview of OO javascript, cross browser issues, being serious and rigorous with your development process and their particular views on how to deploy javascript unobtrusively.

The subsequent 3 chapters are the refresher course. These chapters work through a ton of topics, at times it refers you to sites on the net for further information. He starts the overview with pretty much every topic in OO development, from scope and closures to a remarkably sweet and concise description of context. He brings together all these topics and how together they form the building blocks for javascripts particular flavor of OO. Then he tackles the various ways to deal with inheritance - here he covers ways to do it yourself as well as a couple libraries that you can use. He also talks about packaging and ways to make your code play well with others. He wraps up the overview with a chapter about debugging and testing - a topic I think a bit under-discuessed in javascript and I was happy to get his views and suggestions on how to deal with these.

With those conveniently out of the way he dives right into several chapters where he talks about the DOM, events and css scripting and how they relate to his goal of creating unobtrusive scripts where no javascript intrudes on nice clean html. He covers these topics by presenting a small problem and working through the code to solve that problem. It's very easy to follow and works well. He introduces several libraries to help with the process, but is careful always to explain the fundamentals of how things are actually working under the hood. Too many books that start working with libraries gloss over what's actually happening and wind up being little more than extra documentation for the libraries, fortunately this book doesn't suffer from this problem.

He then goes into two more chapters bringing it all together with larger in depth projects, enhancing forms with validation and other features as well as a javascript image gallery.

The last major part covers Ajax - one chapter goes into nice detail and builds several helpful library functions. He also covers handling the return of these requests and the pros/cons of xml vs html vs json. And then it goes into two bigger projects enhanced blogs, autocomplete and wiki.

Finally, he talks a little about where javascripts going and provides some references for DOM, events and browsers in the appendix.

There's not much negative to say about this. It gives a great overview for those who don't know the language inside and out, it covers a huge number of topics in a very readable and instructive way and gives a very useful reference to DOM and event scripting at the end. It does suffer slightly from putting some code in that is unexplained until a future point in the book. But, it doesn't happen often.

In the days of Ajax, a good understanding of JavaScript is crucial in really understanding how Ajax works. This book by John Resig (developer of JQuery) has written an intermediate - advanced book on JavaScript teaching the reader topics such as object-oriented practices, creating reusable code, DOM, events along with many useable examples. With all the fancy JavaScript libraries out now, it is good to have a book that teaches the reader how to create your own libraries or at least how many of those are create with proper object-based development.

Until Ajax came along (which brought about JS libraries), knowing how to create objects and reusable code wasn't really explained much in books. This book talks about it in the first chapter, where John shows how to create objects via Prototyping, function overloading and using the Object constructor. John also talks about closures, scope, property and method creation and namespacing. All of these topics are found in other languages (C++, Java, VB.NET), but were not really used much in JavaScript until recently. John also covers in detail inheritance (classical and prototypal) and goes through other libraries (YUI, Dojo, Prototype, etc) and how they are created. A very thorough explanation on objects and creating reusable code in JavaScript. Actually this is one of the few books that have covered these topics in such detail. Many other books just skimmed the surface with these topics that made it hard for the newbie to understand.

What current JavaScript book could be published without talking about the DOM. Every book nowadays talks about this topic since everything out on the web seems to use it in on form or another. This book goes in to great detail talking about the DOM with a complete explanation of the basics of what it is, when it can be accessed (waiting for the DOM to load), finding elements on a page, standard DOM methods and 3rd party functions that have been used for years to fill in the gaps of DOM methods that are not available. For instance: addEvent, getElementsByClassName, CSSQuery, JQuery and others. Without a solid foundation of the DOM, many of the cool things that are done on the web today could not be done.

Another important and often not talked about topic is event registration. Chapter 6 of this book goes into the various ways and element can respond to an event. From event phases, (capturing and bubbling), traditional event binding (DOM Level 1) to W3C DOM Binding. This can be a very difficult topic to understand since there are a few differences between the way IE and other browsers handle it. But John explains each difference in great detail and makes you fully aware of how to handle it with some nice examples.

John also covers creating unobtrusive scripts which doesn't assume that JavaScript will be available in the user's browser and how to handle this scenario. This also ties in to separating the three layers (Presentation, Structure and Behavior) which is also discussed. This teaches the user how to keep your inline JS event handling out of the HTML and in a separate .JS file. This makes updating your code easier and less problematic in the future.

The rest of the book focuses on using JavaScript with CSS and applying the previous techniques covered in useful examples such as form validation, creating a dynamic image gallery and some simple Ajax examples.

This is a great book if you know the basics of JavaScript and want to take your skills to the next level and especially if you're not a "true" programming and need a little more explanation. A great book!