DHTML: Learning By Example
Book Review

By Dale Farris, Secretary Golden Triangle PC Club November 2002 "DHTML Learning By Example" is intended for use in a short course focusing on DHTML programming, as a supplement in a course on Web programming, or for self-study. Minimal experience with personal computers is assumed, principally the ability to do basic computer operations such as launch application programs, perform tasks with application programs, and access the Internet. Although a background in computer programming is helpful, it is not necessary. What is called DHTML consists of HTML 4, JavaScript/JScript/ECMA Common Standard, plus Cascading Style Sheets (CSS), the MS Dynamic HTML Object Model, as well as the Microsoft-specific VBScript/ActiveX Controls. DHTML is part of the general computing trend of the '90s, the tendency away from structured programming, with a focus on actions and toward object-based programming (OOP-Object Oriented Programming), where the objects can be compared to nouns in our language. Note that this relatively short work is not designed as a narrative explanation and discussion about DHTML. Author Mellor instead dives right into DHTML programming, and leaves the general discussion about DHTML to the many other fine works on DHTML that could be considered "first reads" on this subject. For those interested in creating DHTML programming, the author has provided exactly what they want in this small package that contains a ton of useful hints, tips, and suggestions in working with DHTML programming. Experience is the best teacher, and author Mellor has created a set of learning exercises that build experience. With access to a PC and a block of time to devote to working through this book, you need only a few days to become adept at DHTML programming operations. Further explanations are found in the appendices, and a list of Web links on DHTML is also provided at the back of the book. The book contains 26 examples, along with many other coding illustrations, with each followed by a detailed explanation. Theory, tips, and new concepts are introduced along the way, both in the body of the text, as well as in the examples. The organization of this textbook emphasizes ease of use by the student, with great attention to the step-by-step process of using the many included DHTML programming selections. This high degree of detail to such tedious organization of this material must have been an enormous challenge to produce, not only for the author, but for all involved in the superb design and organization of this wealth of information. The result is a vastly superior book on how to work with DHTML that will make it much easier to learn this skill. Table of Contents This little book is chock-a-block filled with 26 examples of programming in DHTML, each followed by a detailed explanation. You can also download all code examples and files, and get additional information from the publisher's web site, www.fbeedle.com/dhtmlfiles/dhtml_codes.zip. Rather than be organized in traditional chapters, this book instead focuses on the DHTML code, which results in one main book section that is further divided into the many DHTML code example explanations. The book explains in plain language the elements and attributes in HTML, and shortly compares the 3.2 and 4 versions of HTML to XHTML. The Microsoft Document Object Model (DOM) is introduced, where elements are considered to be objects. The CSS hierarchical model is explored using HTML and XML examples, followed by client-side scripting using JavaScript and VBScript. The last third of the book illustrates "Dynamic Scripting," the combination of CSS, DOM, and JavaScript. You will need IE 4+ for most of the examples, but IE 5+ to work with his Example D. However, this can be displayed in IE 4 if you add the XML parser (called "msxml") which is available from Microsoft. This is the only example where you will need an XML-enabled browser. You can use an ASCII text editor to write the examples of code in the book, or if you prefer, you could work with the free EditPad from Tucows, that can easily be used in conjunction with Windows Explorer and IE. The book covers the basics of CSS and JavaScript 1.1 and 1.2, referring only to JScript where there are significant deviations. You might also be interested in author Mellor's other work on XML:  Learning By Example. Very quickly, readers will see that Mellor's attempt in this powerful book is to eschew narrative explanation, and directly work on numerous examples of DHTML coding, all of which will be of super help to web site developers and programmers working with DHTML. Detailed Key Features Preface DHTML The Various HTMLs and XHTML Cascading Style Sheets - CSS Ex A - Inline Style Ex B - Declared Style in the Style Element Ex C - Linked External Style Sheets The "Cascade" in Cascading Style Sheets Ex D - Linked External CSS in XML Ex E - Absolute Positioning Ex F - Relative Positioning Ex G - Background Color and Background Graphics Ex H - Element Dimensions Summary of CSS: Links Summary of CSS: Selectors Summary of CSS: Pseudo-classes JavaScript Client-side JavaScript Comments in JavaScript JavaScript Objects JavaScript Statements and Variables Variable Types JavaScript Functions JavaScript Operators JavaScript Conditional Statements Ex I - Calling JavaScript Ex J - Object Model and Collections An Overview of Event Handlers Ex K - Variables and Methods Ex L - Functions and Parameters Ex M - Conditional Statements and Loops Ex N - Conditional Statements, Operators, and Standard Functions Home Exercise 1 - Forms and Arrays, a 24-Hour Online Pizza Bar Ex O - Arrays Ex P - Environmental Variables and Browser Check Ex Q - Setting Cookies with JavaScript VBScript Ex R - Data-binding Using Dynamic VBScript Dynamic Styles Ex S - DOM: Specifying the Background Color JavaScript Colors Ex T - Dynamic Positioning Positioning: Length Value Units Home Exercise 2: Dynamic Graphics and Audio: Sniping at Layers Ex U - Dynamic Forms Regular Expressions Ex V - Practical RegExp Home Exercise 3: onFocus, onBlur, and Regular Expressions Ex W - Drop-down Menus Ex X - Movement Using Timer Functions Time-related Properties of the Window Object Ex Y - Pre-loading Mouse-over Effects Home Exercise 4: Pre-loaded Images: and Art Gallery Ex Z - Timed Linked Graphical Sequence The six appendixes include Appendix A, "Keyword Reference," Appendix B, "Overview of Objects," Appendix C, "Overview of Methods," Appendix D, "Overview of Properties," Appendix E, "Further Information on the Internet," and Appendix F, "FAQs." About the Author Robert B. Mellor teaches at the IT University of Copenhagen. He has 15 years of teaching experience in several countries and is Examiner at many universities all over the world. Target Readers This is one of the most succinctly organized books on DHTML you will find on the market. The approach here is to offer a super collection of useful DHTML examples in a book that is a certainty for any class in DHTML. Mellor's super text is tailor-made for any university or college class in DHTML, and it can stand alone as the sole text for such a class, or as a marvelous supplement to other programming language texts. The book is designed to serve both the self-paced learner, as well as students enrolled in DHTML classes, and I think the use of Mellor's super guidebook will most assuredly be of great benefit in the classroom. With his inclusion of extensive DHTML examples, this will greatly speed up the DHTML coding experience for students. As a core textbook in an DHTML class, students will find this book a marvelous learning tool, especially those new to DHTML coding, or even HTML coding. As most experienced programmers know, learning any programming language is quite tedious and laborious, and will not naturally be easily grasped. This results in slow going in many programming classes, and in the case of learning DHTML, Mellor's many super examples of DHTML programming, line by line by line, will certainly be well received by students. A special note for instructors of these classes is worthy here. In addition to the high value you will receive from using this textbook, Franklin, Beedle & Associates, Inc. (FBA) also makes available superb instructor resource materials that will provide everything you need to integrate the use of this text in a class. I have greatly benefited from these many helpful materials in preparing for my own class that uses another FBA textbook, and I can highly recommend this publisher to others wishing to develop a class in Java. With this venture, the Franklin, Beedle & Associates, Inc. publishing company solidifies their rapidly growing reputation for producing excellent textbooks for computer classes that can be considered by all levels of education. Students working toward computer certification, as well as any other student, should seriously consider this superb book that thoroughly covers how to create Java programs. Recommendation Author Mellor and publisher Franklin Beedle & Associates, Inc. have designed a super, concise work on DHTML that will be well received by students. The text is designed for students with little or no prior programming experience, as well as for students who have experience with another programming language. For any DHTML class, this textbook can well serve any instructor looking for a well organized collection of DHTML examples. The book will also be of value to others interested in learning DHTML, but not necessarily wanting to enroll in a class. However, self-paced learners will naturally need to also be self-disciplined enough to walk through the many included exercises, while understanding that without an instructor working with the additional instructor material they will not necessarily have readily available this type of assistance, or answers to their questions. Book Contents 173 pages; preface; extensive programming examples; tables; appendixes; index ISBN 1st Edition, 2003 1-887902-83-X List Price $14.95 Supplemental Code Included In Book All the many DHTML programming examples included in the textbook are also accessible at Franklin, Beedle & Associates, Inc.'s web site, www.fbeedle.com/dhtmlfiles/dhtml_codes.zip. At this site, you can download all the different examples in different files, for easy loading in your web browser. This alone is worth the minimal investment in this powerful book that is a sure bet for any DHTML class. Publisher Contact: Christine Collier Marketing Representative Franklin, Beedle & Associates, Inc. 8536 SW St. Helens Drive, Suite D Wilsonville, Oregon 97070 1-800-FBA-BOOK 1-503-682-7668 FAX 1-503-682-7638 ccollier@fbeedle.com www.fbeedle.com