Charlie Calvert''''s C++ Builder Unleashed doc

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Charlie Calvert's Borland, C++Builder Unleashed (Imprint: SAMS) Publication Date: Author: Charles Calvert ISBN: 0-672-31022-8 Overview Part I Getting Started 1 Introduction to C++Builder 2 Basic Facts about C++Builder 3 C++Builder and the VCL 4 Events 5 Exceptions 6 Sharing Code Between Delphi and C++Builder 7 Graphics Part II Relational Databases 8 Database Basics and Database Tools 9 Using TTable and TDataSet 10 SQL and the TQuery Object 11 Working with Field Objects 12 Understanding Relational Databases 13 Flat-File, Real-World Databases 14 Sessions and Relational Real-World Databases Part III Client/Server Databases 15 Working with the Local InterBase Server 16 Advanced InterBase Concepts 17 Printing: QuickReport and Related Technologies 18 Working with CASE Tools: Cadet, ER1, and SDesigner Part IV Creating Components 19 Inheritance file:///C|/temp/Book%20-%20HTML%20-%20Programming% %20Borland%20C++%20Builder%20Unleashed/ewtoc.html (1 of 2)01-09-2003 00:27:34 developer.com - Reference 20 Encapsulation 21 Polymorphism 22 Creating Descendants of Existing Components 23 Creating Components from Scratch 24 Creating Non-Visual Components Part V Internet and Distributed OLE 25 Using WININET to Create FTP Applications 26 Extending an Internet Server with ISAPI 27 Distributed COM Part VI Win32 and Multimedia 28 Game Programming 29 Game Engines file:///C|/temp/Book%20-%20HTML%20-%20Programming% %20Borland%20C++%20Builder%20Unleashed/ewtoc.html (2 of 2)01-09-2003 00:27:34 Charlie Calvert's C++ Builder Unleashed Charlie Calvert's Borland® C++Builderô Acknowledgments As always, I want to extend my deepest and most heartfelt thanks to my wife Margie. Without her, I doubt if I ever would have gotten interested in computers, nor would I have found the patience and strength to write books about them. I am the one who writes the text and works out nearly all the sample programs, but there are many other people who helped bring this book to print. My debt is portioned evenly between the technical people at Borland who found time to answer my questions, and the editors at Sams and Borland who helped format the text and search for errors. A particular debt of gratitude is owed to the expert Borland programmers who took the time to talk theory with me. Getting a good technical answer to a specific question is one thing, but getting the benefit of someone's understanding of the significance and structure of a subject is even more important. On the BCB side, I want to thank Bruneau Babet, Ellie and Jeff Peters, Roland Fernandez, Lar Mader, John Wiegley, Evan Scott, Matt Lawrence, Peter Sollich, Eli Boling, Dave Wilhelm, Conrad Herman, Taylor Hutt, Sergie Cardosa, John Thomas, and Pete Williams for their help. I want to extend a special thanks to Maurice Barnum for his tireless patience in answering some of the most difficult of my many technical questions. On the VCL side, I would like to thank Danny Thorpe, Steve Trefethen, Steve Teixeira, Alain Tadros, Allen Bauer, Gary Whizin, Bill Weber, Mark Sikes, Lance Devin, David Intersimone, and Zack Urlocker for all their patience in answering my many questions and for their good work in support of the VCL. I would like to extend a special thanks to Chuck Jazdzewski for finding time to answer questions and for the tremendous work he has done in making the VCL such a success. The VCL is the result of the output from many talented programmers, but if I were forced to single out the one person who made the biggest contribution, that would have to be Chuck. Thanks to Kari Marcussen for her talent and help with the art in the DirectX examples. Thanks to John Thomas, Jeff Cottingham, and Stuart Fullmer for their help porting the DirectX components from Object Pascal to C++. I would like to thank Tamara Meyer, Kurt Hecht, Yolanda Davis, CJ Martin, Ellen Lawson, and Nancy file:///C|/temp/Book%20-%20HTML%20-%20Programming %20Borland%20C++%20Builder%20Unleashed/htm/fm.htm (1 of 3)01-09-2003 00:27:42 Charlie Calvert's C++ Builder Unleashed Collins for making my day-to-day life manageable. A special thanks goes to Karen Giles for her good heart and hard work. As always, I want to thank the people at Sams who work so hard to make these books readable. Chris Denny is the sole of patience and even temper when he deals with me regularly on the phone. Thanks also to Mary Inderstrodt, Rich Alvey, and all the other Sams employees who worked so hard on this book. None of my books would be even half as readable were it not for the efforts of the editors and technicians at Sams who work on layout, structure, and grammar. Thanks to readers from all around the world whose feedback inspires me to keep writing. Thanks also to everyone in the computer industry who stays in the game because of their love of the technology. In the short term, it appears that money, flash, and marketing are the forces that drive the industry. In the long run, however, the people who really shape the future of computers are the technicians and scientists who write code and dream dreams. I am in the debt of everyone who sits down to write code or who takes the time to discuss programming seriously in books, articles, and newsgroups. There is definitely a worldwide community of programmers who exist outside the boundaries of individual nations. This book is merely a small part of that community's continuous, ongoing dialog. Charlie Calvert users.aol.com/charliecal Santa Cruz, CA March, 1997 About the Author Charlie Calvert Charlie Calvert is the author of Teach Yourself Windows 95 Programming in 21 Days, Delphi 2 Unleashed, and Turbo Pascal Programming 101. His day job is at Borland International, where he works as a manager in Developer Relations. In the past, he has also worked as a journalist and English teacher. He lives with his wife Margie in Santa Cruz, CA. Tell Us What You Think! As a reader, you are the most important critic and commentator of our books. We value your opinion and want to know what we're doing right, what we could do better, what areas you'd like to see us publish in, and any other words of wisdom you're willing to pass our way. You can help us make strong books that meet your needs and give you the computer guidance you require. Do you have access to CompuServe or the World Wide Web? Then check out our CompuServe forum by typing GO SAMS at any prompt. If you prefer the World Wide Web, check out our site at http:// www.mcp.com. file:///C|/temp/Book%20-%20HTML%20-%20Programming %20Borland%20C++%20Builder%20Unleashed/htm/fm.htm (2 of 3)01-09-2003 00:27:42 Charlie Calvert's C++ Builder Unleashed NOTE: If you have a technical question about this book, call the technical support line at 317-581-3833. As the publishing manager of the group that created this book, I welcome your comments. You can fax, e-mail, or write me directly to let me know what you did or didn't like about this book as well as what we can do to make our books stronger. Here's the information: Fax: 317-581-4669 E-mail: programming_mgr@sams.samspublishing.com Mail: Greg Wiegand Sams Publishing 201 W. 103rd Street Indianapolis, IN 46290 file:///C|/temp/Book%20-%20HTML%20-%20Programming %20Borland%20C++%20Builder%20Unleashed/htm/fm.htm (3 of 3)01-09-2003 00:27:42 Ch 1 Introduction to C++Builder Charlie Calvert's C++ Builder Unleashed - 1 - Introduction to C++Builder Overview In this chapter I introduce Borland C++Builder (BCB) and explain what it is about. I also devote considerable time to explaining the purpose of this book and the philosophy behind my approach to technical writing. Technical subjects covered in this chapter include ● Creating a simple Multimedia RAD program that plays movies, WAV files, and MIDI files. ● Shutting down the BCB RAD programming tools and writing raw Windows API code instead. ● Creating components dynamically on the heap at runtime. ● Setting up event handlers (closures) dynamically at runtime. ● A brief introduction to using exceptions. This topic is covered in more depth in Chapter 5, "Exceptions." ● A brief introduction to ANSI strings. This subject is covered in more depth in Chapter 3, "C++Builder and the VCL." ● Using the online help. ● Greping through the include and source files that come with the product and with this book. This chapter includes sample programs or code snippets illustrating all of these concepts. The sample programs for this chapter are found on the CD that accompanies this book in the directory called Chap01. The same pattern is followed for all other chapters. For instance, the code for Chapter 2, "Basic Facts About C++Builder," is in a subdirectory on the CD called Chap02. Getting in the Mood Programming is part of an esoteric world where logic is sacred. Even if you understand exactly why a program works, there is still a magical element involved. Things appear and disappear. Objects materialize, and then dematerialize. They do so according to strictly defined logical rules; but still, there is the fact that things appear and disappear right before our eyes. file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%20C++%20Builder%20Unleashed/htm/ch01.htm (1 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C++Builder To be a good programmer, you have to be a wizard. You have to study arcane material, sit up over it until your eyes are bleary, and ponder its meaning, seeking to understand its mysteries. Many people never understand the subtleties of programming. They don't ever penetrate to the inner mysteries of this challenging field. But think of the joy you feel when you finally figure it out! The profound satisfaction of actually cracking the code, mastering the spells, and seeing through to the inner mystery! The arcane minutiae of programming is part of a subtle, intricate world that can be mastered only by a few dedicated souls who are willing to work hard to get at the inner truth of an algorithm, of an object hierarchy, of a coding technique. Some products seem to be effective at capturing the essence of the beautiful, mysterious logic that underlies the world of programming. C++ has always had free entry into this realm. C++Builder, however, raises the ante in the C++ world by allowing you to create programs with a powerful set of tools that gracefully augment your programming skills. BCB is one of the first serious compilers that allows you to pick up objects called components with the mouse and move them around so that you can change the logic of your program visually, rather than solely with code. The core of this technology is component programming not large, bloated, difficult to create components but small, sleek, easy-to-build components that run at lightning speed, components that appear and disappear before your eyes at the click of a mouse. Programming is intellectually exciting. At times, it's even dreaded word fun! C++Builder puts the excitement back in C++ programming. If you like to write fast programs that are easy and fun to use, this is the right tool for you. Best of all, C++Builder gives you full access to all the advanced features of C++, including templates, name spaces, operator overloading, and the entire Windows API, including cutting-edge APIs such as DirectX, OLE Automation, and ActiveX. Most of the time, BCB programming is surprisingly easy. On occasion, it's very challenging. It is, however, always interesting and exciting. Let other programmers plod along with boring compilers made by some huge soulless conglomerate full of middle managers who middle-manage their products into one giant, boring access violation. There is something different about BCB. Like its cousin Delphi, it has something of the true spark of the real programmer's art in its sleek lines, in its fast compilation, and in its subtle and artful use of the C++ language. The Audience for This Book Throughout this book, I walk a subtle line between extremes. Sometimes the text has pulled me in the direction of system programming, and at other times I have relied on the RAD tools that make BCB so easy to use. At times, I have wanted to find the fastest way to perform a particular task and at others I have wanted to find the clearest, simplest way to perform a task. Almost a third of the book concentrates on database tasks, but I also dig deeply into OOP, component creation, and esoteric Windows APIs such as DirectX. C++ is the language of choice for programmers obsessed with speed, who long to optimize their programs down to the last clock cycle, and who love to plumb the most intricate depths of the computer. Some C++ programmers feel physical pain when they have to give up clock cycles that could be optimized out given sufficient time. In short, C++ is a language designed for creating operating systems and compilers. file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%20C++%20Builder%20Unleashed/htm/ch01.htm (2 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C++Builder RAD tools, on the other hand, are designed for programmers who have a job to do and want to get it done quickly. These people want a safety net so they don't crash and burn! They are willing to give up clock cycles in return for usable code. In short, RAD programmers are intent on getting a job done quickly and safely, whereas C++ programmers are traditionally intent on creating the smallest, fastest programs possible. This book, and BCB as a whole, is about the meeting of these two diverse camps. I am very much aware that many C++ programmers won't like the "smell" of RAD, and that many RAD programmers will be appalled by the ornate subtleties of C++. However, I believe that there is a place where these two groups can meet, and furthermore, I think C++ can provide the high productivity tools that RAD programmers expect, along with the high performance, system-loving, optimized intricacies that true aficionados of C++ demand. In short, this book is for contemporary programmers who practice their art on the cutting edge of modern programming techniques. That does not mean that this book is about the most technical aspects of C++ and Windows, nor does it mean that this book is about a dangerous, new form of programming that wastes clock cycles indiscriminately. Instead, this book is about techniques that allow systems programmers to get their work done quickly, while allowing RAD programmers to speed up and enhance their programs. I should perhaps add that a large portion of this book is dedicated to client/server database programmers. Nearly 80 percent of the applications made today involve databases, and this tool will undoubtedly be used very heavily by client/server developers. I go into considerable lengths to talk about the advanced database features found in BCB; I cover SQL, stored procedures, triggers, filters, lookups, and numerous other database techniques. BCB Versus VB There is one thing that ought to be made clear right at the start. The programs you write with BCB are comparable in terms of size and performance with the programs you create with OWL or MFC. It would be a mistake to assume that BCB has any of the limitations you find in VB or PowerBuilder, or even in Optima. Anything you can do in MSVC or in BC5 you can also do in BCB, and you can do it with the same, or an increased, degree of subtlety and artfulness. Both BCB and VB are RAD tools. But that is where the comparison between the two products must end. VB is a nice product, but it is not a serious programming tool. BCB is a very serious programming tool. It is a real C++ compiler that comes with all the bells and whistles. The presence of RAD tools can lead you to believe that BCB is somehow crippled in terms of performance or capability. However, that is an erroneous conclusion. If you take the time to explore the product in depth, you will find that it lacks nothing in terms of power or capability. The RAD tools in this package add no real overhead to your programs that you would not find in either OWL or MFC. The VCL is comparable to OWL and MFC in every way, except for the fact that it is much easier to use and much more elegantly designed. The word component can also conjure up images of slow, buggy, hard-to-understand ActiveX controls. BCB file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%20C++%20Builder%20Unleashed/htm/ch01.htm (3 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C++Builder components are much faster, much smaller, and much easier to make than ActiveX controls. OLE is a powerful technology and one that I use quite frequently but it lacks the subtlety, speed, and elegance of the VCL code that underlies BCB. A Cautious Approach to Programming Having gone to some lengths to emphasize the technical depth of BCB, I want to turn around and discuss the relatively conservative approach I take to the art of writing programs. I have been writing code long enough to have grown suspicious of techniques that are too fancy, too subtle, and too hard to parse, execute, and maintain. As a result, I have adopted the style of programming championed by people who want to write safe, easy-to-maintain programs. I tend to promote a conservative programming style and indeed, almost all the good programmers I know use these same techniques, even when writing code that is designed for high performance applications. A certain degree of caution is necessary if you want to write robust code. When in doubt, I always err on the side of caution. Does this mean I want you to write slow, bloated code? No, of course not! My goal is to walk that fine line between writing code that is such a high wire act that it can't be maintained, and writing code that is so high- level, so abstracted, that its performance becomes an abomination. BCB is about the place you can get the maximum in terms of safety, without giving up significant power in terms of speed and flexibility. It's about walking the line between two extremes. On Using C++ When creating the sample applications for this book, I tried to choose code that walks the middle line between being too cautious and too daring. I tried to take the best ideas from the C++ language and combine them with the benefits of RAD. I want to get far enough into C++ to leverage its power, without going so far that I spend whole chapters parsing the subtleties of some obscure syntactical corner of the language. I also want to use many high-level, RAD-based tools, but I don't want to rely on them so completely that they overshadow the power of the C++ language. The goal is to find the middle ground, the artful line that yields the best programs. If I am in doubt, I will err on the side of the RAD programmers who have a job to do. The primary reason for this decision is simply that there are already many great books out there on the intricacies of C++ and on the subtleties of the Windows API. There is no need for another book on those subjects. Instead, I want to show what C++Builder brings to the table. When exploring BCB, however, I will always keep at least one eye on the system programmer. I know what you want, I believe in your cause, and I want to show you how BCB can help you complete even the subtlest jobs more quickly than traditional environments such as BC5 or MSVC. My promise is that the executables you produce with BCB will be at least as small, and at least as fast as the executables you produce with MFC or file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%20C++%20Builder%20Unleashed/htm/ch01.htm (4 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C++Builder OWL. And, if you want, you can cut out BCB's object-oriented tools and produce tiny executables that match anything that you can do with BC5 or MSVC. I am not trying to create a companion volume to a classic hard-core tome such as the Zen of Assembly Language, More Effective C++, Undocumented Windows, the ARM, or Inside Windows. Books like that have their place, of course, but that is not the kind of programming I want to write about. Clearly, I am trying to set practical, reasonable goals for this book. However, I don't mean to imply that this is a plodding, methodical book that will never take flight into any interesting subjects. On the contrary, I want to show how you can do fancy, flashy, exciting things with a computer, without having to parse the lowest-level bits in the operating system. If you want to plumb to the lowest depths of the operating system, I will take you right up to the edge, show you how to get started, and then wish you Godspeed. You can use BCB to do some great system programming, but I will leave the specifics of how to proceed to other authors, or to a second book of my own on the subject. This book contains lots of exciting code on subjects such as multimedia, games, and Internet programming. I concentrate on very high-performance tools such as DirectX and on cutting-edge technologies such as OLE. Unlike other books on these subjects, however, my goal is to show how you can integrate these things into your projects even if you are on a tight schedule and even if you would not normally be inclined to do the kind of spelunking that those names imply. In my opinion, the kind of programming described in this book is the essence of cutting-edge computer technology (at the time of this writing). The best programmers today use whatever tools they can find to allow them to quickly produce high-performance programs. Plumbing the depths is fun, but it loses some of its appeal when the Internet calls, or when you need to produce an inventory program quickly, or when you want to spice up an application so that your users actually enjoy sitting down to work with one of your creations. My point is quite simply that today many of the best programmers are specializing, not in plumbing the depths of the operating system, but in producing real-world applications quickly. This is an advanced programming book that assumes a good deal of experience on the part of the reader. However, I want your experience to be not deep and narrow, but broad and expansive. Humility, Crooked Timber, and the Practical Programmer In the book Code Complete (published by Microsoft Press), Steve McConnell quotes an award-winning paper by Edsger Dijkstra called the "The Humble Programmer." I regard this work as one of the guiding lights of this book. I would much rather write a humble program that works well than be involved in a flashy, ego-ridden project that is never finished, or that ships two years late. The key to getting things done is to show a little humility. In particular, if you work under the assumption that any one programmer is perfect, you are doomed to failure. Computers are reliable; programmers make mistakes. Computers, on the other hand, look remarkably dense when compared to the creativity a good programmer can file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%20C++%20Builder%20Unleashed/htm/ch01.htm (5 of 50)01-09-2003 00:27:55 [...]... cover this kind of material in this book, but it might be helpful to file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/ch01.htm (15 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C+ +Builder hear one description of how to use the C+ +Builder visual tools in hyper-mode If you grasp the subtleties of this technique, you will find that you do not need to manually... Project: Muli-media RAD // Copyright (c) 1997 by Charlie Calvert #include #pragma hdrstop #include "Main.h" #pragma resource "*.dfm" TForm1 *Form1; fastcall TForm1::TForm1(TComponent* Owner) file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/ch01.htm (10 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C+ +Builder : TForm(Owner) { } void fastcall TForm1::Load1Click(TObject... with or other programmers or, if you prefer, sell it to other programmers file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/ch01.htm (22 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C+ +Builder Tools like Visual Basic or PowerBuilder gave people the mistaken impression that RAD was innately slow and perhaps designed for programmers who didn't really know how... (c) 1997 by Charlie Calvert #define STRICT #define WIN32_LEAN_AND_MEAN #include #include #pragma warning (disable: 4068) #pragma warning (disable: 4100) static char szAppName[] = "Window1"; static HWND MainWindow; file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/ch01.htm (23 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C+ +Builder LRESULT... find ways to program that are safe! If I have the humility to admit I am not perfect, I can file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/ch01.htm (6 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C+ +Builder start making programs that work and that get turned in on time! Once again, I don't really care about my manager's schedule; I care about my schedule... Open menu item to select an AVI file."); ShowMessage("Bummer: " + E.Message + " " + S); } } file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/ch01.htm (11 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C+ +Builder void fastcall TForm1::Exit1Click(TObject *Sender) { Close(); } void fastcall TForm1::ChangeBackground1Click(TObject *Sender) { AnsiString RootDir(ParamStr(0));... screen for the Multimedia Adventure program The RAD Tasks for Creating the Multimedia Program file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/ch01.htm (12 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C+ +Builder To create the program, bring up BCB and select New Application from the File menu Drop down the following components on the main form: TPanel *Panel1;... Width = 485 Height = 301 Align = alClient Picture.Data = { Lots of numbers omitted here } end file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/ch01.htm (13 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C+ +Builder object Panel1: TPanel Left = 0 Top = 0 Width = 485 Height = 41 Align = alTop TabOrder = 0 object MediaPlayer1: TMediaPlayer Left = 192 Top = 5 Width... fsEdit Filter = `Movies, Sound, Midi|*.avi;*.wav;*.mid' InitialDir = `c:\' Left = 48 Top = 48 end file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/ch01.htm (14 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C+ +Builder end You can convert your forms into this kind of text by right-clicking them and selecting View as Text from a popup menu Conversely, you can translate... programming models more carefully in later chapters In particular, Chapter 2 and Chapter 3 go into file:///C|/temp/Book%20-%20HTML%20-%20Programming 0Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/ch01.htm (7 of 50)01-09-2003 00:27:55 Ch 1 Introduction to C+ +Builder considerable depth on the subject of VCL, how it works, and why it exists On Using the Visual Tools Before I get started with a specific programming . %20Borland%2 0C++% 2 0Builder% 2 0Unleashed/ ewtoc.html (2 of 2)01-09-2003 00:27:34 Charlie Calvert's C++ Builder Unleashed Charlie Calvert's Borland® C+ +Builder Acknowledgments As. %20Borland%2 0C++% 2 0Builder% 2 0Unleashed/ htm/fm.htm (3 of 3)01-09-2003 00:27:42 Ch 1 Introduction to C+ +Builder Charlie Calvert's C++ Builder Unleashed -