tailieunhanh - JavaScript Bible, Gold Edition part 108

JavaScript Bible, Gold Edition part 108. This book will bring programmers and non-technical professionals, including casual programmers and scripters, painlessly up to speed on all aspects of mastering JavaScript. Key topics include programming fundamentals, JavaScript language elements and how to use them effectively, and how to easily and efficiently add powerful new functionality to HTML documents and Java applets. | XML Objects XML eXtensible Markup Language is an undeniably hot topic in the Internet world. Not only has the W3C organization formed multiple working groups and recommendations for XML and its offshoots but the W3C DOM recommendation also has XML in mind when it comes to defining how elements attributes and data of any kind not just the HTML vocabulary are exposed to browsers as an object model. Most of the arcana of the W3C DOM Core specification especially the structure based on the node are in direct response to the XML possibilities of documents that are beginning to travel the Internet. While XML documents can stand alone as containers of structured data in both IE5 and NN6 the Windows version of IE5 permits XML data to be embedded as islands in an HTML document. Such islands are encased in an XML element an IE-specific extension of HTML. It s important to distinguish between the XML element the element generated in a document by the IE-specific XML tag set and a generic XML element that is a part of the XML data island. Generic XML elements have tag names that are meaningful to a data application and they are usually defined by a separate Document Type Declaration DTD that contains a formal specification of the element names their attributes if any and the nature of the data they can contain. Out of necessity this book assumes that you are already familiar with XML such that your server-based applications serve up XML data exclusively embed XML islands into HTML documents or convert database data into XML. The focus of this chapter and an extended application example of Chapter 57 is how to access custom elements that reside inside an IE XML element. Elements and Nodes Once you leave the specialized DOM vocabulary of HTML elements the world can appear rather primitive a highly granular world of node hierarchies elements element attributes and node data. This granularity is a necessity in an environment in which the elements are far from generic and the .