Visual C++ .NET Developer’s Guide John Paul Mueller McGraw-Hill/Osborne 2600 Tenth Street Berkeley, California 94710 U.S.A. To arrange bulk purchase discounts for sales promotions, premiums, or fund-raisers, please contact McGraw-Hill/Osborne at the above address. For information on translations or book distributors outside the U.S.A., please see the International Contact Information page immediately following the index of this book. Copyright © 2002 by The McGraw-Hill Companies. All rights reserved. Printed in the United States of America. Except as permitted under the Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher, with the exception that the program listings may be entered, stored, and executed in a computer system, but they may not be reproduced for publication. 1234567890 CUS CUS 01987654321 Book p/n 0-07-213262-0 and CD p/n 0-07-213282-5 parts of ISBN 0-07-213281-7 Publisher Brandon A. Nordin Vice President & Associate Publisher Scott Rogers Acquisitions Editor Ann Sellers Project Editor Katie Conley Acquisitions Coordinator Tim Madrid Technical Editor Bill Burris Copy Editor Carl Wikander Proofreader Carol Burbo Indexer Irv Hershman Computer Designers Tara A. Davis, Lauren McCarthy Illustrators Michael Mueller, Greg Scott, Lyssa Wald Cover Illustration Eliot Bergman Cover Series Design Greg Scott This book was composed with Corel VENTURA™ Publisher. Information has been obtained by McGraw-Hill/Osborne from sources believed to be reliable. However, because of the possibility of human or mechanical error by our sources, McGraw-Hill/Osborne, or others, McGraw-Hill/Osborne does not guarantee the accuracy, adequacy, or completeness of any information and is not responsible for any errors or omissions or the results obtained from use of such information. This book is dedicated to Micah Schlobohm. I appreciate her kindness, thoughtfulness, and desire to help. She’s the kind of friend that more people should have, but unfortunately don’t. About the Author John Mueller is a freelance author and technical editor. He has writing in his blood, having produced 53 books and over 200 articles to date. The topics range from networking to artificial intelligence, and from database management to heads down programming. Some of his current books include a SOAP developer guide, a small business and home office networking guide, and a Windows 2000 Performance, Tuning, and Optimization book. His technical editing skills have helped over 25 authors refine the content of their manuscripts. John has provided technical editing services to both Data Based Advisor and Coast Compute magazines. He’s also contributed articles to magazines like SQL Server Professional, Visual C++ Developer, and Visual Basic Developer. He is currently the editor of the .NET electronic newsletter for Pinnacle Publishing. When John isn’t working at the computer, you can find him in his workshop. He’s an avid woodworker and candle maker. On any given afternoon, you can find him working at a lathe or putting the finishing touches on a bookcase. One of his newest craft projects is making glycerin soap, which comes in handy for gift baskets. You can reach John on the Internet at [email protected]. John is also setting up a Web site at: http://www.mwt.net/~jmueller/; feel free to look and make suggestions on how he can improve it. One of his current projects is creating book FAQ sheets that should help you find the book information you need much faster. Acknowledgments Thanks to my wife, Rebecca, for working with me to get this book completed. I really don’t know what I would have done without her help in researching and compiling some of the information that appears in this book (especially the Glossary). She also did a fine job of proofreading my rough draft and page proofing the final result. Bill Burris deserves thanks for his technical edit of this book. He greatly added to the accuracy and depth of the material you see here. I really appreciate the time he devoted to checking my code for accuracy. Bill also supplied some of the URLs you see in the book and other helpful tips and hints. Matt Wagner, my agent, deserves credit for helping me get the contract in the first place and taking care of all the details that most authors don’t really consider. I always appreciate his help. It’s good to know that someone wants to help. Finally, I would like to thank Ann Sellers, Timothy Madrid, Katie Conley, Carl Wikander, and the rest of the production staff at McGraw-Hill/Osborne for their assistance in bringing this book to print. I especially appreciate Ann’s patience when things didn’t go exceptionally well. Tim provided me with many thought-provoking messages and was always willing to talk with me when I needed help. Introduction Unless you’ve been hiding in a cave in a remote part of the earth, Microsoft has inundated you with news of .NET by now. Microsoft’s marketing machine is working overtime, as usual, to ensure you don’t miss their latest and greatest product. If you listen to the Microsoft hype, it seems that they expect everyone to drop billions (trillions?) of lines of code and adopt .NET tomorrow. What the hype doesn’t mention is that adopting .NET completely means starting from scratch. The real world is a different place than the fantasyland of Microsoft hype. In the real world, developers have to maintain existing code at the lowest possible cost and still produce new applications in record time. The task seems impossible when you have two completely different technologies to develop these applications. On the one hand, you have the realm of MFC and the Win32 API. On the other hand, you have the new .NET Framework. Which do you choose for a given task? Answering the question of which technology to use is one of the biggest problems this book will tackle. We’ll discuss how to use the old, the new, and, most importantly, the mixed environments of Visual C++ .NET. Knowing when .NET can actually help you create an application faster is the key to managing application development in an environment where you have two different architectures to consider. Microsoft’s .NET Framework is an exciting new technology for a developer looking for every productivity enhancement available. My purpose in writing this book is to help you balance the usefulness of this new technology against the need to maintain existing code. By the time you complete this book, you’ll not only know how to work with .NET to create some relatively complex applications, but you’ll better understand when .NET is a good choice for application development. What’s in This Book Visual C++ .NET Developer’s Guide contains a mix of theory and programming examples, with a heavy emphasis on the programming examples. You’ll find a mix of Win32, MFC, ATL, and .NET code within the book. In some cases, I’ll show you how to mix an existing technology with a new one—Visual C++ .NET is definitely a transitional language, one that will help you move from Win32 application development to .NET. Here’s a brief overview of the six parts of this book. Part I—Visual C++ in General This part of the book introduces you to some of the new features in Visual C++ .NET. We’ll also discuss some basic programming principles. You’ll learn how to create various types of applications. Most of the code in this part is unmanaged. However, this part includes some managed code examples that show how you’d create the same result as an unmanaged counterpart using the .NET Framework. You’ll also learn some advanced coding processes in this part of the book. We’ll discuss threads in Chapter 3, and I’ll show you how to create two types of threads. The graphics programming examples in Chapter 4 include both static graphics and animated graphics using GIFs. Chapter 5 will help you understand the intricacies of Active Directory, while Chapter 6 shows how to create components using both ATL and MFC. Part II—Visual C++ .NET and Database Management Database management is an essential part of every business today. Chapter 7 of this part tells you about the various technologies and indicates when you can best use them to your advantage. We also look at how to create and use DSNs. Chapter 8 is the unmanaged coding example for this part. You’ll learn how to use OLE-DB to create a basic database application that includes a form view, printing, and search routines. This section of the book also tells you how to get around certain problems with the Visual C++ .NET environment. For example, Visual C++ .NET doesn’t ship with all of the controls found in Visual Studio 6. Some of your applications might require these controls, so I show how to install them. Unfortunately, some controls won’t work even if you do install them, and I show you how to get around some of these problem areas. Chapter 9 is the managed coding example for this part. We discuss ODBC .NET in this chapter. Unfortunately, ODBC .NET wasn’t ready in time for the book, so you won’t see a coding example. We’ll create a managed example using ADO .NET that includes use of the new DataGrid control (among others). This section also shows how to create a print routine and other database application basics. Part III—Visual C++ and Online Computing Distributed applications are becoming more prominent as businesses move to the Internet in an effort to remain connected with partners, employees, and customers. This part of the book shows you how to work with SOAP and discusses Web Services in general. You’ll also learn how to work with alternative devices such as PDAs. Chapter 10 contains a simple ASP.NET example that helps you understand the benefits of this technology. Chapter 11 shows you how to create both ISAPI Filters and ISAPI Extensions as well as a SOAP application that relies on the Microsoft SOAP Toolkit. Most of the examples in this part of the book rely on unmanaged programming techniques. Part IV—Visual C++ .NET and Microsoft.NET Most of the examples in this part of the book rely on managed programming techniques. You’ll learn how to create various types of managed applications that rely exclusively on the .NET Framework. Chapter 12 is unique because it compares Visual C++ .NET to C# and even provides an example in both languages for comparison purposes. This is also the chapter to read if you want to learn how to move your applications to .NET. Chapter 13 is your key for learning about the new attributed programming techniques provided with Visual C++ .NET. Attributes greatly reduce the coding burden for the developer. Examples in this chapter use both managed and unmanaged coding techniques. Chapter 14 shows you how to work with managed components. You’ll also create a custom attribute and use reflection to read its contents from the compiled application. Part V—The Developer View of Visual C++ .NET This part of the book contains a mix of topics that didn’t fit well anywhere else, but are extremely important for the developer. Chapter 15 discusses the inner workings of Security within Windows 2000 and Windows XP. Security is an important topic in a world where crackers make it their business to test your applications for holes in every way possible. Chapter 16 shows how to create administration tools for your applications. Most complex applications require some type of configuration and “tweaking” as part of the installation and maintenance cycle. Using the Microsoft Management Console (MMC) to maintain your application makes sense because it reduces the user interface design burden for the developer and reduces the amount of code required to create the management program. Chapter 17 shows you how to create various types of help files. Microsoft is always moving on to some new form of help, but sometimes you need to use the older forms of the help file as well. This chapter shows how to create both. Finally, Chapter 18 shows how to package your application once you finish building it. Part VI—Appendixes and Glossary This last part of the book contains two appendixes and a glossary. Appendix A tells you how to get the best deal for your next component purchase. It also helps you find some “must have” components for your next application. Appendix B is an online resource guide that helps you locate additional information about Visual C++ .NET. Sometimes it’s good to know where to find additional help. Finally, the Glossary contains a complete list of every esoteric term and acronym used in the book. What You’ll Need There are some assumptions that I’ve made while writing the application programming examples in this book. You need at least two machines: a workstation and a server. This two-machine setup is the only way that you’ll see Visual C++ .NET in action and truly know it works as anticipated. In addition, your development workstation and server must meet the minimum .NET requirements (and hopefully provide more than the minimum). You might experience problems with the database and other large examples when running a minimal machine configuration. During the writing of this book, I used a Windows 2000 and Windows XP workstation. There’s no guarantee that any of the code in the book will work with Windows 9x; although, most of it will. The server was loaded with Windows 2000 Server with the latest patches and service packs installed. You’ll need a Pocket PC compatible PDA to work with the SOAP example in Chapter 10. You must install the latest service packs for all products before the examples will work properly. .NET is a new technology and relies on the latest versions of many DLLs and the .NET Framework. Note Many of the concepts you’ll learn in this book won’t appear in your online documentation. Some of it is so new that it appears only on selected Web sites. You’ll find either a tip or a note alerting you to the location of such information throughout the book. In addition, Microsoft made some material available only through selected channels, like an MSDN subscription. Other pieces of information are simply undocumented, and you won’t find them anywhere except within a newsgroup when someone finds the feature accidentally. I tested all of the examples in this book with Visual C++ .NET Enterprise Architect Edition. Microsoft made a considerable number of changes to Visual C++ .NET, so none of the examples will load in previous versions of the product, even if the code will compile. None of these examples are guaranteed to work with any other programming language products, and none of them will work with the educational versions Visual Studio. Some of the example programs rely on a database manager. I used Microsoft Access for all of the examples in this book for the sake of simplicity. The source code CD contains copies of all of the databases used in this book. Conventions Used in This Book In this section we’ll cover usage conventions. This book uses the following conventions: [<Filename>] When you see square brackets around a value, switch, or command, it means that this is an optional component. You don’t have to include it as part of the command line or dialog field unless you want the additional functionality that the value, switch, or command provides. <Filename> A variable name between angle brackets is a value that you need to replace with something else. The variable name you’ll see usually provides a clue as to what kind of information you need to supply. In this case, you’ll need to provide a filename. Never type the angle brackets when you type the value. ALL CAPS There are three places you’ll see ALL CAPS: commands, filenames, and case-sensitive registry entries. Normally, you’ll type a command at the DOS prompt, within a PIF file field, or within the Run dialog field. If you see ALL CAPS somewhere else, it’s safe to assume that the item is a case- sensitive registry entry or some other value like a filename. File | Open Menus and the selections on them appear with a vertical bar. “File | Open” means “Access the File menu and choose Open.” italic There are three places you see italic text: new words, multi- value entries, and undefined values. You’ll always see a value in italic whenever the actual value of something is unknown. The book also uses italic where more than one value might be correct. For example, you might see FILExxxx0 in text. This means that the value could be anywhere between FILE0000 and FILE9999. monospace It’s important to differentiate the text that you’ll use in a macro or type at the command line from the text that explains it. This book uses monospace type to make this differentiation. Every time you see monospace text, you’ll know that the information you see will appear in a macro, within a system file like CONFIG.SYS or AUTOEXEC.BAT, or as something you’ll type at the command line. You’ll even see the switches used with Windows commands in this text. There is another time you’ll see monospace text. Every code listing uses monospaced code to make the text easier to read. Using monospaced text also makes it easier to add things like indentation to the coding example. URLs URLs will normally appear highlighted so that you can see them with greater ease. The URLs in this book provide sources of additional information designed to make your development experience better. URLs often provide sources of interesting information as well. Icons This book contains many icons that help you identify certain types of information. The following paragraphs describe the purpose of each icon. Note Notes tell you about interesting facts that don’t necessarily affect your ability to use the other information in the book. I use note boxes to give you bits of information that I’ve picked up while using Visual C++, Windows 9x, Windows 2000, or Windows XP. Tip Everyone likes tips, because they tell you new ways of doing things that you might not have thought about before. Tip boxes also provide an alternative way of doing something that you might like better than the conventional (first) approach I provided. Caution This means watch out! Cautions almost always tell you about some kind of system or data damage that’ll occur if you perform certain actions (or fail to perform others). Make sure you understand a caution thoroughly before you follow any instructions that come after it. Browser Alert The Internet contains a wealth of information, but finding it can be difficult, to say the least. Web Links help you find new sources of information on the Internet that you can use to improve your programming or learn new techniques. You’ll also find newsgroup Web Links that tell where you can find other people to talk with about Visual C++. Finally, Web Links will help you find utility programs that’ll make programming faster and easier than before. What Happened to Hungarian Notation? At one time, Hungarian notation was an essential for developers because the IDEs provided with early compilers didn’t tell you much about the variables, methods, and other programming constructs in your application. Today, IDEs commonly provide detailed information about the constructs in your application and even help you to make good decisions about formatting your code. Hungarian notation has become a verbose method of writing code that addresses a problem that doesn’t exist anymore. For the most part, this book doesn’t use Hungarian notation. The variable names you see describe the purpose of the variable, rather than the variable type. You might see a bit of Hungarian notation floating around in places where I felt it would help, but these uses are minimal.