tailieunhanh - DHTML Utopia Modern Web Design Using JavaScript & DOM- P2

DHTML Utopia Modern Web Design Using JavaScript & DOM- P2:In a single decade, the Web has evolved from a simple method of delivering technical documents to an essential part of daily life, making and breaking relationships and fortunes along the way. “Looking something up on the Internet,” by which is almost always meant the Web, is now within reach of almost anyone living in a first-world country, and the idea of conducting conversations and business (and probably orchestras) in your Web browser is no longer foreign, but part of life | xiv Licensed to siowchen@ 1 DHTML Technologies The White Rabbit put on his spectacles. Where shall I begin please your Majesty he asked. Begin at the beginning the King said gravely andgo on till you come to the end then stop. Lewis Carroll Alice s Adventures in Wonderland Dynamic HTML called DHTML for short is the name given to a set of Web development techniques that are mostly used in Web pages that have non-trivial user-input features. DHTML means manipulating the Document Object Model of an HTML document fiddling with CSS directives in style information and using client-side JavaScript scripting to tie everything together. In this introductory chapter I ll provide a brief overview of some of the things you ll need to know about the building blocks that make up DHTML Websites. You ll find it useful reading if you need to refresh your memory. If you already know all these details you might want to flick through the chapter anyway you may even be a little surprised by some of it. In the coming pages we ll come to understand that DHTML is actually a combination of proper HTML for your content Cascading Style Sheets for your design and JavaScript for interactivity Mixing these technologies together can result in a humble stew or a grandiose buffet. It s all in the art of cooking so let s start rattling those pots and pans Licensed to siowchen@ Chapter 1 DHTML Technologies HTML Starting Points Websites are written in HTML. If you re reading this book you ll almost certainly know what HTML is and will probably be at least somewhat experienced with it. For a successful DHTML-enhanced Website it s critical that your HTML is two things valid and semantic. These needs may necessitate a shift away from your previous experiences writing HTML. They may also require a different approach than having your preferred tools write HTML for you. Step up to Valid HTML A specific set of rules set out in the HTML recommendation1 dictate how HTML should be written. .