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ActionScript 3 for Flash, Flex, and AIR
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Essential ActionScript 3.0 (Essential) (Essential)Essential ActionScript 3.0 (Essential) (Essential) by Colin Moock
Buy new: $34.64 / Used from: $23.65
Colin Moock wrote the definitive reference for ActionScript 2.0. This book is a complete rewrite and definitely essential.
ActionScript 3.0 Cookbook: Solutions for Flash Platform and Flex Application DevelopersActionScript 3.0 Cookbook: Solutions for Flash Platform and Flex Application Developers by Joey Lott
Buy new: $26.39 / Used from: $21.85
The author covers most of the things you'll want to do with ActionScript 3 in no-nonsense form, with code examples for everything.
Foundation Actionscript 3.0 Animation: Making Things Move!Foundation Actionscript 3.0 Animation: Making Things Move! by Keith Peters
Buy new: $26.39 / Used from: $21.14
A surprisingly good guide to procedural animation in Flash or Flex.
Advanced ActionScript 3 with Design PatternsAdvanced ActionScript 3 with Design Patterns by Joey Lott
Buy new: $31.49 / Used from: $22.49
If you're working on larger projects or a bunch of them you'll benefit from using and reusing these ActionScript design patterns.
ActionScript 3.0 Design Patterns: Object Oriented Programming Techniques (Adobe Developer Library)ActionScript 3.0 Design Patterns: Object Oriented Programming Techniques (Adobe Developer Library) by William Sanders
Buy new: $40.37 / Used from: $13.25
Another useful Design Patterns book for ActionScript 3.0.
Programming Flex 2: The Comprehensive Guide to Creating Rich Internet Applications with Adobe Flex (Programming)Programming Flex 2: The Comprehensive Guide to Creating Rich Internet Applications with Adobe Flex (Programming) by Chafic Kazoun
Buy new: $34.64 / Used from: $4.59
You can write Flex 2 programs without using much ActionScript, but the more you know the more powerful your programs will be. This book is a great starting point for Flex 2.
The Essential Guide to Flex 2 with ActionScript 3.0The Essential Guide to Flex 2 with ActionScript 3.0 by Charles E Brown
Buy new: $29.99 / Used from: $5.33
Another good Flex 2 resource.
Professional Adobe Flex 2 (Programmer to Programmer)Professional Adobe Flex 2 (Programmer to Programmer) by Rich Tretola
Buy new: $36.70 / Used from: $0.28
A comprehensive guide to Flex 2 with lots of ActionScript 3 samples.
Apollo for Adobe Flex Developers Pocket GuideApollo for Adobe Flex Developers Pocket Guide by Mike Chambers
Buy new: $11.69 / Used from: $0.94
Apollo is now AIR, and this book was written for a prior release of the product. However most of it still applies. Plus I helped write it. Look for it online too.
Object-Oriented ActionScript 3.0Object-Oriented ActionScript 3.0 by Todd Yard
Buy new: $31.49 / Used from: $14.10
The ActionScript 2 version of this book was very handy, so I'm sure the ActionScript 3 version will be well worth your while. If you're new to object-oriented programming this is a good starting point.
ActionScript 3.0 Game Programming UniversityActionScript 3.0 Game Programming University by Gary Rosenzweig
Buy new: $31.49 / Used from: $31.63
I haven't read this yet, but it looks interesting. I always like to promote game programming in Flash and Flex.
Foundation ActionScript 3.0 with Flash CS3 and Flex (Foundation)Foundation ActionScript 3.0 with Flash CS3 and Flex (Foundation) by Todd Yard
Buy new: $26.39 / Used from: $25.03
The first books focusing on ActionScript 3 with Flash CS3 are just coming out. This looks like a good one to try.
ActionScript 3.0 for Adobe Flash CS3 Professional Hands-On TrainingActionScript 3.0 for Adobe Flash CS3 Professional Hands-On Training by Todd Perkins
Buy new: $31.49 / Used from: $29.00
Another good Flash CS3 and ActionScript 3 resource.