XML Programming Using the Microsoft XML Parser

Transcription

1 XML Programming Using the Microsoft XML Parser SOD MEE FOO AND WEI MENG LEE APress Media, LLC

2 XML Programming Using the Microsoft XML Parser Copyright 2002 by Soo Mee Foo and Wei Meng Lee Originally published by Apress in 2002 All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the prior written permission of the copyright owner and the publisher. ISBN ISBN (ebook) DOI / Trademarked names may appear in this book. Rather than use a trademark symbol with every occurrence of a trademarked name, we use the names only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark. Editorial Directors: Dan Appleman, Peter Blackburn, Gary Cornell, Jason Gilmore, Karen Watterson Technical Reviewer: Ronald Landers Managing Editor: Grace Wong Project Managers: Alexa Stuart, Erin Mulligan Development Editor: Kenyon Brown Copy Editors: Kit Cooley Production Editor: Kari Brooks Compositor: Impressions Book and Journal Services, Inc. Artist: Kurt Krames Indexer: Rebecca Plunkett Cover Designer: Tom Debolski Marketing Manager: Stephanie Rodriguez The information in this book is distributed on an "as is" basis, without warranty. Although every precaution has been taken in the preparation of this work, neither the author nor Apress shall have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the information contained in this work. The source code for this book is available to readers at the Downloads section. You will need to answer questions pertaining to this book in order to successfully download the code.

3 Contents at a Glance About the Authors.... xi About the Technical Reviewer.... xi Acknowledgments.... xiii Introduction.... xiv Chapter 1: Introduction to the Extensible Markup Language (XML)... 1 Chapter 2: Addressing XML Parts Using XPath Chapter 3: The Extensible Stylesheet Language Transformation (XSL T) Chapter 4: The Document Object Model (DOM) Chapter 5: Support of XML in ActiveX Data Objects (ADO) 2.1 and Above Chapter 6: XML Support in SQL Server Chapter 7: Simple API for XML (SAX) Chapter 8: XML Schemas Chapter 9: The Wireless Markup Language (WML) Chapter 10: Simple Object Access Protocol (SOAP) and Web Services Appendix A: Installing Microsoft XML Tools Appendix B: Document Object Model (DOM) Level 1 Core Interfaces Appendix C: XML-Data Reduced (XDR) Schema Index iii

4 Contents About the Authors.... xi About the Technical Reviewer.... xi Acknowledgments.... xiii Introduction... xiv Chapter 1: Introduction to the Extensible Markup Language (XML)... l W3( and XML... 2 Basic XML Terminology... 6 Rules of XML... 6 Document Type Definition (DTD) (DATA and P(DATA Elements or Attributes XML Schemas XML Encoding and Unicode Namespaces XML Parsers Microsoft XML Parser (MSXML) Uses and Benefits of XML XML and Web Browser Support Using the Microsoft XML Parser Release 3.0 SPl XML Editors Useful Web Links Summary Chapter 2: Addressing XML Parts Using XPath XPath Expression XPath Data Model Location Path Functions Abbreviated Syntax Useful Web Links Summary v

5 Contents Chapter 3: The Extensible Stylesheet Language Transformation (XSL T) Motivation for XSLT Support of XS L T in MSXML A First Look at XSL T XSLT Fundamentals Client-Side versus Server-Side XSL T Transformation Useful Web Links Summary Chapter 4: The Document Object Model (DOM) Introduction to DOM XML DOM Parsers Support of DOM in MSXML Representing XML Document as a Tree Creating a DOM Tree of an XML Document in Memory Saving a DOM Tree Fundamental APIs for Processing a DOM Tree Client-Side DOM Programming-Shopping Cart Server-Side DOM Programming-Shopping Cart Useful Web Links Summary Chapter 5: Support of XML in ActiveX Data Objects (ADO) 2.1 and Above Universal Data Access The ADO Object Model Connection Object Recordset Object Command Object Record Object Stream Object Error Handling Case Study: Updating Book Prices Using Three-Tier Architecture Useful Web Links Summary vi

6 Contents Chapter 6: XML Support in SQL Server Additional Software Installation and Configuration Retrieving and Transforming Rowset Data into XML Data Providing Rowset Data from XML Data Using the OPENXML Provider Accessing SQL Server Using HTTP Persisting Changes Using Updategram Useful Web Links Summary Chapter 7: Simple API for XML (SAX) An Alternative to DOM SAX in MSXML Error Handling in SAX Using SAX When Do You Use SAX? Useful Web Links Summary Chapter 8: XML Schemas XML Schema and XDR Schema First Look at XML Schema XML Schema Data Types Groupings Linking Schemas and Redefining Definitions Documenting the Schema Using <annotation> Tools for Validating XML Schemas Useful Web Links Summary vii

7 Contents Chapter 9: The Wireless Markup Language (WML) Architecture of WAP Understanding the Wireless Markup Language (WML) Testing WML Applications Tailoring WAP Content with XML and XSLT Using the Microsoft XSL ISAPI Useful Web Links Summary Chapter 10: Simple Object Access Protocol (SOAP) and Web Services Introduction to SOAP Web Services Creating a Web Service Consuming a Web Service Developing Web Services Using the Microsoft SOAP Toolkit Version Providing Web Services Using the SOAP Toolkit: A Case Study Web Services Security Useful Web Links Summary Appendix A: Installing Microsoft XML Tools Installing IE Tools for Validating XML Documents Checking the Version of the Installed XML Parser Appendix B: Document Object Model (DOM) Level 1 Core Interfaces Understanding Basic Terms in the DOM Fundamental Interfaces Extended Interfaces viii

8 Contents Appendix c: XML-Data Reduced (XDR) Schema Basic Elements in XDR Schema General Layout Specification of the Content Model Data Types Annotations Index ix

9 About the Authors Wei Meng Lee currently holds a full-time job as a lecturer at the School of Information and Communications Technology, Ngee Ann Polytechnic (Singapore). Besides teaching, he offers consultant services to the industry and conducts in-house training in the areas of Web development. He is also a contributing author to magazines like XML Journal, XML Magazine, and.net Magazine, and he is the co-author of Beginning WAP, WML and WMLScript (Wrox) and Dynamic WAP Application Development (Manning). A frequent speaker at developer conferences and seminars, Wei Meng spoke at the Wrox Professional Wireless Developer Conference (July 2000, Amsterdam) and Wireless Developer Conference (December 2000, San Jose). Contact Wei Meng at wei _ meng_lee@hotmail.com. Soo Mee Foo is currently lecturing at Ngee Ann Polytechnic (Singapore) in Web technologies and security. She also conducts workshops for IT professionals and is involved in designing Web-based courseware and industrial projects. She is a co-author of Beginning WAP, WML and WMLScript and Dynamic WAP Application Development. Soo Mee can be contacted at soomee _ foo@hotmail. com. About the Technical Reviewer Ronald Landers is the owner of Right -Click Consulting, LLC, a Los Angeles-based consulting, development, and training firm. The company specializes in Microsoft -based technologies including Active Server Pages, SQL Server, Visual Basic, Internet Explorer, and XML. Mr. Landers is a faculty member and instructor at UCLA Extension and has been teaching and consulting for the past 12 years. xi

10 Acknowledgments FIRST AND FOREMOST I want to thank Gary Cornell for giving us this opportunity to write this book. I actually met Gary at the Wireless Developer Conference in San Jose in December After a few exchanges, Gary took the bold step and said, "Let's go into contract." The rest, they say, is history. Thank you, Gary! The folks at Apress have been very helpful and encouraging, especially our editorial director, Jason Gilmore. Jason has been very patient with us throughout the writing stage, offering many suggestions to improve our writing early in the project. I also want to express my heartfelt thanks to folks like Kenyon Brown, Erin Mulligan, Kit Cooley, Kari Brooks, Grace Wong, and the many unnamed heroes who have worked tirelessly to turn our raw manuscript into one that we are proud of. I also wish to express my gratitude to our technical editor, Ron Landers, who has definitely made this book a better read by his many suggestions. Special thanks to XML Journal and XML Magazine for permission to use some of the articles of mine that they have published. A big thanks to Altova for supplying me with their superb XMLSpy software suite for evaluation and testing during the writing of this book. You guys have solid technical support! Last, but not least, I want to thank my co-author Soo Mee for making this book a reality. And of course, my family has always been my strongest support. -Wei Meng Lee I would like to take this opportunity to thank Gary Cornell for his trust in us to write this book. I would also like to thank the great team of people that helped bring this book into reality. Specifically, I express thanks to Jason Gilmore for his encouragement and help in getting the book started, which is always a hurdle at the beginning. Also, my utmost thanks go to Alexa Stuart, Erin Mulligan, Kenyon Brown, Kit Cooley, Kari Brooks, Stephanie Rodriguez, and Grace Wong, who certainly need tremendous patience to work with me, and who have undoubtedly worked very hard to keep the schedule especially during the festive season. My sincere thanks here to Wei Meng, who has never forgotten to institute fun into this writing project. Last, but not least, thanks to my family for being understanding at all times. -SooMeeFoo xiii

11 Introduction MOST XML BOOKS in the market today fall into two main categories: They either focus just on the theoretical aspects of the language, or they contain everything related to XML and weigh more than five kilograms! When we first taught XML to beginners, we wanted to find a book that covered just enough ofxml without overwhelming them. We looked for a book that covered not just the fundamentals ofxml, but one that also contained the most importantxml-related technologies. Not only that, the book had to illustrate some of the practical uses ofxml in the real world. We.realized that we had to produce a book that targeted beginning to intermediate XML programmers. As trainers, we know the importance of a book that explains concepts clearly and contains concrete code examples illustrating the theory just explained. We carefully reviewed the various XML technologies and specifications that are available today, and in the end, we decided on the most common XML technologies in use today: XPath, XSLT, DOM, SAX, XML in SQL Server, WML, SOAP and XML Schema. During the writing of this book, a couple of new Microsoft products were launched. Most notably, Microsoft released the.net Framework and Visual Studio.NET for public beta testing. In addition, the Microsoft XML parser has since matured to version 4 as this book goes into print. The release of these products was important to this book. First, we have based our concepts and code on Microsoft XML Parser 3.0. However, the release of version 4 does not alter the concepts we have covered in this book; version 4 offers better performance and adds some new features. Second, Visual Studio.NET has made developing and consuming Web services very simple. It takes care of generatingwsdl files and class proxies automatically. Contrast this to using the SOAP Toolkit for developing and consuming Web services (which is covered in this book), developing Web services using VS.NET seems a trivial task. However, our approach in this book is to show how all the building blocks of Web services are built and assembled. Readers who have used the SOAP Toolkit would then be well positioned to build Web services using any tools and platform. Writing a book on XML is like shooting a moving target. The XML standards are always changing, and new specifications come and go. We hope you will enjoy this book as much as we have enjoyed writing it! xiv