visual basic 6 - the complete reference 1999

Introduction MCSD Training Guide: Visual Basic 6 Exams is designed for developers with the goal of certification as a Microsoft Certified Solutions Developer (MCSD). It covers both the Designing and Implementing Distributed Applications with Microsoft Visual Basic 6.0 exam (70-175) and the Designing and Implementing Desktop Applications with Microsoft Visual Basic 6.0 exam (70-176). These exams measure your ability to design and implement distributed and desktop application solutions by using Microsoft Visual Basic version 6.0. This book is your one-stop shop. Everything you need to know to pass the exams is in here, and Microsoft has approved it as study material. You do not have to take a class in addition to buying this book to pass the exam. However, depending on your personal study habits or learning style, you may benefit from buying this book and taking a class. This book also can help advanced users and administra- tors who are not studying for the exam but are looking for a single-volume reference on Microsoft’s TCP/IP implementation. HOW THIS BOOK HELPS YOU This book conducts you on a self-guided tour of all the areas covered by the VB6 Distributed Applications exam and the VB6 Desktop Applications exam and teaches you the specific skills you need to achieve your MCSD certification. You’ll also find helpful hints, tips, real-world examples, exercises, and references to addi- tional study materials. Specifically, this book is set up to help you in the following ways: á Organization. This book is organized by individual exam objectives. Every objective you need to know for the VB6 Distributed Applications exam and the VB6 Desktop Applications exam is covered in this book. The objectives are not covered in exactly the same order as they are listed by Microsoft, but we have attempted to organize the topics in the most logical and accessible fashion to make it as easy as possible for you to learn the information. We have also attempted to make the information accessible in the following ways: • The full list of exam topics and objectives is included in this introduction. • Each chapter begins with a list of the objectives to be covered. Each objective is also identified as one that applies to the Distributed Applications exam, the Desktop Applications exam, or both. • Each chapter also begins with an outline that pro- vides you with an overview of the material and the page numbers where particular topics can be found. • We also repeat objectives before where the mater- ial most directly relevant to it is covered (unless the whole chapter addresses a single objective). • Information on where the objectives are covered is also conveniently condensed on the tear card at the front of this book. á Instructional Features. This book has been designed to provide you with multiple ways to learn and rein- force the exam material. Following are some of the helpful methods: 02 002-8 Intro 3/1/99 7:45 AM Page 1 2 MCSD TRAINING GUIDE: VISUAL BASIC 6 EXAMS • Objective Explanations. As mentioned previ- ously, each chapter begins with a list of the objectives covered in the chapter. In addition, immediately following each objective is an explanation in a context that defines it more meaningfully. • Study Strategies. The beginning of the chapter also includes strategies for approaching the studying and retaining of the material in the chapter, particularly as it is addressed on the exam. • Exam Tips. Exam tips appear in the margin to provide specific exam-related advice. Such tips may address what material is covered (or not covered) on the exam, how it is covered, mnemonic devices, or particular quirks of that exam. • Review Breaks and Summaries. Crucial infor- mation is summarized at various points in the book in lists or tables. Each chapter ends with a summary as well. • Key Terms. A list of key terms appears at the end of each chapter. • Notes. These appear in the margin and contain various kinds of useful information such as tips on technology or administrative practices, historical background on terms and technolo- gies, or side commentary on industry issues. • Warnings. When using sophisticated informa- tion technology, there is always the potential for mistakes or even catastrophes that occur because of improper application of the tech- nology. Warnings appear in the margin to alert you to such potential problems. • In-depths. These more extensive discussions cover material that may not be directly relevant to the exam but which is useful as reference material or in everyday practice. In-depths may also provide useful background or contextual information necessary for understanding the larger topic under consideration. • Step by Steps. These are hands-on, tutorial instructions that lead you through a particular task or function relevant to the exam objectives. • Exercises. Found at the end of the chapters in the “Apply Your Knowledge” section, exercises may include additional tutorial material as well as other types of problems and questions. • Case Studies. Presented throughout the book, case studies provide you with a more concep- tual opportunity to apply and reinforce the knowledge you are developing. They include a description of a scenario, the essence of the case, and an extended analysis section. They also reflect the real-world experiences of the authors in ways that prepare you not only for the exam but for actual network administra- tion as well. á Extensive practice test options. The book pro- vides numerous opportunities for you to assess your knowledge and practice for the exam. The practice options include the following: • Review Questions. These open-ended questions appear in the “Apply Your Knowledge” section at the end of each chapter. They allow you to quickly assess your comprehension of what you just read in the chapter. Answers to the questions are provided later in the section. 02 002-8 Intro 3/1/99 7:45 AM Page 2 INTRODUCTION 3 • Exam Questions. These questions also appear in the “Apply your Knowledge” section. They reflect the kinds of multiple-choice questions that appear on the Microsoft exams. Use them to practice for the exam and to help you determine what you know and what you need to review or study further. Answers and explanations for them are provided. • Practice Exam. A Practice Exam is included in the “Final Review” section. The Final Review section and the Practice Exam are discussed below. • Top Score. The Top Score software included on the CD-ROM provides further practice questions. It also provides you with valuable exam-day tips and information on new exam/question formats such as adaptive tests and simulation- based questions. • Practice Exam. A full practice test for each of the exams is included. Questions are written in the styles used on the actual exams. Use it to assess your readiness for the real thing. The book includes several valuable appendices as well, including a glossary (Appendix A), an overview of the Microsoft certification program (Appendix B), and a description of what is on the CD-ROM (Appendix C). The Microsoft VB exams assume an elementary knowl- edge of VB but do not specify this knowledge in the exam objectives. For that reason, this book includes Appendix E, “Visual Basic Basics” that provides you with an overview of the elementary VB knowledge and skills that are not specified as objectives but that you will need to know in order to pass the exam. Finally, Appendix F provides you with a list of “Suggested Readings and Resources” that provides you with useful information on Visual Basic 6. These and all the other book features mentioned previ- ously will provide you with thorough preparation for the exam. For more information about the exam or the certifica- tion process, contact Microsoft: Microsoft Education: 800-636-7544 Internet: ftp://ftp.microsoft.com/Services/MSEdCert World Wide Web: http://www.microsoft.com/train_cert CompuServe Forum: GO MSEDCERT NOTE For a complete description of the New Riders Top Score test engine, please see Appendix D, “Using the Top Score Software.” á Final Review. This part of the book provides you with three valuable tools for preparing for the exam. • Fast Facts. This condensed version of the information contained in the book will prove extremely useful for last-minute review. • Study and Exam Tips. Read this section early on to help you develop study strategies. 02 002-8 Intro 3/1/99 7:46 AM Page 3 4 MCSD TRAINING GUIDE: VISUAL BASIC 6 EXAMS WHAT THE DESIGNING AND IMPLEMENTING DISTRIBUTED APPLICATIONS WITH MICROSOFT VISUAL BASIC 6.0 EXAM (70-175) COVERS The Designing and Implementing Distributed Applications with Microsoft Visual Basic 6.0 Exam (70-175) covers the nine main topic areas represented by the conceptual groupings of the test objectives: Developing the Conceptual and Logical Design, Deriving the Physical Design, Establishing the Development Environment, Creating User Services, Creating and Managing COM Components, Creating Data Services, Testing the Solution, Deploying the Application, and Maintaining and Supporting an Application. Each of these main topic areas is covered in one or more chapters. The exam objectives are listed by topic area in the following sections. Developing the Conceptual and Logical Design Given a conceptual design, apply the principles of modular design to derive the components and services of the logical design. Deriving the Physical Design Assess the potential impact of the logical design on per- formance, maintainability, extensibility, scalability, availability, and security. Design Visual Basic components to access data from a database in a multitier application. Design the properties, methods, and events of components. Establishing the Development Environment Establish the environment for source-code version control. Install and configure Visual Basic for developing distributed applications. Configure a server computer to run Microsoft Transaction Server (MTS). á Install MTS. á Set up security on a system package. Configure a client computer to use an MTS component. á Create packages that install or update MTS components on a client computer. Creating User Services Implement navigational design. á Dynamically modify the appearance of a menu. á Add a pop-up menu to an application. á Create an application that adds and deletes menus at runtime. á Add controls to forms. á Set properties for controls. á Assign code to a control to respond to an event. 02 002-8 Intro 3/1/99 7:46 AM Page 4 INTRODUCTION 5 Create data input forms and dialog boxes. á Display and manipulate data by using custom controls. Controls include TreeView, ListView, ImageList, Toolbar, and StatusBar. á Create an application that adds and deletes controls at runtime. á Use the Controls collection to manipulate controls at runtime. á Use the Forms collection to manipulate forms at runtime. Write code that validates user input. á Create an application that verifies data entered at the field level and the form level by a user. á Create an application that enables or disables controls based on input in fields. Write code that processes data entered on a form. á Given a scenario, add code to the appropriate form event. Events include Initialize, Terminate, Load, Unload, QueryUnload, Activate, and DeActivate. Add an ActiveX control to the toolbox. Create dynamic Web pages by using Active Server Pages (ASP) and Web classes. Create a Web page by using the DHTML Page Designer to dynamically change attributes of elements, change content, change styles, and position elements. Use data binding to display and manipulate data from a data source. Instantiate and invoke a COM component. á Create a Visual Basic client application that uses a COM component. á Create a Visual Basic application that handles events from a COM component. Create callback procedures to enable asynchronous pro- cessing between COM components and Visual Basic client applications. Implement online user assistance in a distributed appli- cation. á Set appropriate properties to enable user assis- tance. Help properties include HelpFile, HelpContextID, and WhatsThisHelp. á Create HTML Help for an application. á Implement messages from a server component to a user interface. Implement error handling for the user interface in dis- tributed applications. á Identify and trap runtime errors. á Handle inline errors. á Determine how to send error information from a COM component to a client computer. Use an active document to present information within a Web browser. Creating and Managing COM Components Create a COM component that implements business rules or logic. Components include DLLs, ActiveX controls, and active documents. Create ActiveX controls. á Create an ActiveX control that exposes properties. á Use control events to save and load persistent properties. 02 002-8 Intro 3/1/99 7:46 AM Page 5 6 MCSD TRAINING GUIDE: VISUAL BASIC 6 EXAMS á Test and debug an ActiveX control. á Create and enable property pages for an ActiveX control. á Enable the data-binding capabilities of an ActiveX control. á Create an ActiveX control that is a data source. Create an active document. á Use code within an active document to interact with a container application. á Navigate to other active documents. Design and create components that will be used with MTS. Debug Visual Basic code that uses objects from a COM component. Choose the appropriate threading model for a COM component. Create a package by using the MTS Explorer. á Use the Package and Deployment Wizard to create a package. á Import existing packages. á Assign names to packages. á Assign security to packages. Add components to an MTS package. á Set transactional properties of components. á Set security properties of components. Use role-based security to limit use of an MTS package to specific users. á Create roles. á Assign roles to components or component interfaces. á Add users to roles. Compile a project with class modules into a COM component. á Implement an object model within a COM component. á Set properties to control the instancing of a class within a COM component. Use Visual Component Manager to manage components. Register and unregister a COM component. Creating Data Services Access and manipulate a data source by using ADO and the ADO Data control. Access and manipulate data by using the Execute Direct model. Access and manipulate data by using the Prepare/Execute model. Access and manipulate data by using the Stored Procedures model. á Use a stored procedure to execute a statement on a database. á Use a stored procedure to return records to a Visual Basic application. Retrieve and manipulate data by using different cursor locations. Cursor locations include client-side and server- side. Retrieve and manipulate data by using different cursor types. Cursor types include forward-only, static, dynamic, and keyset. Use the ADO Errors collection to handle database errors. 02 002-8 Intro 3/1/99 7:46 AM Page 6 INTRODUCTION 7 Manage database transactions to ensure data consis- tency and recoverability. Write SQL statements that retrieve and modify data. Write SQL statements that use joins to combine data from multiple tables. Use appropriate locking strategies to ensure data integrity. Locking strategies include read-only, pes- simistic, optimistic, and batch optimistic. Testing the Solution Given a scenario, select the appropriate compiler options. Control an application by using conditional compilation. Set Watch expressions during program execution. Monitor the values of expressions and variables by using the Immediate window. á Use the Immediate window to check or change values. á Use the Locals window to check or change values. Implement project groups to support the development and debugging processes. á Debug DLLs in process. á Test and debug a control in process. Given a scenario, define the scope of a watch variable. Deploying an Application Use the Package and Deployment Wizard to create a setup program that installs a distributed application, registers the COM components, and allows for unin- stall. Register a component that implements DCOM. Configure DCOM on a client computer and on a server computer. Plan and implement floppy disk-based deployment or compact disc-based deployment for a distributed appli- cation. Plan and implement Web-based deployment for a dis- tributed application. Plan and implement network-based deployment for a distributed application. Maintaining and Supporting an Application Implement load balancing. Fix errors and take measures to prevent future errors. Deploy application updates for distributed applications. WHAT THE DESIGNING AND IMPLEMENTING DESKTOP APPLICATIONS WITH MICROSOFT VISUAL BASIC 6.0 EXAM (70-176) COVERS The Designing and Implementing Distributed Applications with Microsoft Visual Basic 6.0 Exam (70-176) covers the nine main topic areas represented by the conceptual groupings of the test objectives: Developing the Conceptual and Logical Design, Deriving the Physical Design, Establishing the Development Environment, Creating User Services, 02 002-8 Intro 3/1/99 7:46 AM Page 7 8 MCSD TRAINING GUIDE: VISUAL BASIC 6 EXAMS Creating and Managing COM Components, Creating Data Services, Testing the Solution, Deploying the Application, and Maintaining and Supporting an Application. Each of these main topic areas is covered in one or more chapters. The exam objectives are listed by topic area in the following sections. Deriving the Physical Design Assess the potential impact of the logical design on per- formance, maintainability, extensibility, and availability. Design Visual Basic components to access data from a database. Design the properties, methods, and events of com- ponents. Establishing the Development Environment Establish the environment for source-code version control. Install and configure Visual Basic for developing desk- top applications. Creating User Services Implement navigational design. á Dynamically modify the appearance of a menu. á Add a pop-up menu to an application. á Create an application that adds and deletes menus at runtime. á Add controls to forms. á Set properties for controls. á Assign code to a control to respond to an event. Create data input forms and dialog boxes. á Display and manipulate data by using custom controls. Controls include TreeView, ListView, ImageList, Toolbar, and StatusBar. á Create an application that adds and deletes controls at runtime. á Use the Controls collection to manipulate controls at runtime. á Use the Forms collection to manipulate forms at runtime. Write code that validates user input. á Create an application that verifies data entered at the field level and the form level by a user. á Create an application that enables or disables controls based on input in fields. Write code that processes data entered on a form. á Given a scenario, add code to the appropriate form event. Events include Initialize, Terminate, Load, Unload, QueryUnload, Activate, and DeActivate. Add an ActiveX control to the toolbox. Create a Web page by using the DHTML Page Designer to dynamically change attributes of elements, change content, change styles, and position elements. Use data binding to display and manipulate data from a data source. Instantiate and invoke a COM component. á Create a Visual Basic client application that uses a COM component. á Create a Visual Basic application that handles events from a COM component. 02 002-8 Intro 3/1/99 7:46 AM Page 8 INTRODUCTION 9 Create callback procedures to enable asynchronous processing between COM components and Visual Basic client applications. Implement online user assistance in a desktop application. á Set appropriate properties to enable user assis- tance. Help properties include HelpFile, HelpContextID, and WhatsThisHelp. á Create HTML Help for an application. á Implement messages from a server component to a user interface. Implement error handling for the user interface in desktop applications. á Identify and trap runtime errors. á Handle inline errors. Creating and Managing COM Components Create a COM component that implements business rules or logic. Components include DLLs, ActiveX controls, and active documents. Create ActiveX controls. á Create an ActiveX control that exposes prop- erties. á Use control events to save and load persistent properties. á Test and debug an ActiveX control. á Create and enable Property Pages for an ActiveX control. á Enable the data-binding capabilities of an ActiveX control. á Create an ActiveX control that is a data source. Create an active document. á Use code within an active document to interact with a container application. á Navigate to other active documents. Debug a COM client written in Visual Basic. Compile a project with class modules into a COM component. á Implement an object model within a COM component. á Set properties to control the instancing of a class within a COM component. Use Visual Component Manager to manage components. Register and unregister a COM component. Creating Data Services Access and manipulate a data source by using ADO and the ADO Data control. Testing the Solution Given a scenario, select the appropriate compiler options. Control an application by using conditional com- pilation. Set Watch expressions during program execution. Monitor the values of expressions and variables by using the Immediate window. á Use the Immediate window to check or change values. á Use the Locals window to check or change values. 02 002-8 Intro 3/1/99 7:46 AM Page 9 10 MCSD TRAINING GUIDE: VISUAL BASIC 6 EXAMS Implement project groups to support the development and debugging processes. á Debug DLLs in process. á Test and debug a control in process. Given a scenario, define the scope of a watch variable. Deploying an Application Use the Package and Deployment Wizard to create a setup program that installs a desktop application, regis- ters the COM components, and allows for uninstall. Plan and implement floppy disk-based deployment or compact disc-based deployment for a desktop appli- cation. Plan and implement Web-based deployment for a desk- top application. Plan and implement network-based deployment for a desktop application. Maintaining and Supporting an Application Fix errors and take measures to prevent future errors. Deploy application updates for desktop applications. HARDWARE AND SOFTWARE YOU’LL NEED A self-paced study guide, this book was designed with the expectation that you will use VB 6.0 Enterprise Edition as you follow along through the exercises while you learn. However, almost all the exercises can also be completed with the Professional Edition. If you only have the Learning Edition, you’ll be able to do some of the exercises and examples, but many sections will not be directly accessible to you. Your computer should meet the following criteria: á On the Microsoft Hardware Compatibility List á 486DX2 66Mhz (or better) processor á 340MB (or larger) hard disk á 3.5-inch 1.44MB floppy drive á VGA (or Super VGA) video adapter á VGA (or Super VGA) monitor á Mouse or equivalent pointing device á Double-speed (or faster) CD-ROM drive (optional) á Network Interface Card (NIC) á Presence on an existing network, or use of a 2-port (or more) miniport hub to create a test network á Any version of Microsoft Windows capable of running Visual Studio 6.0 á Internet access with Internet Explorer (not necessary for all sections) It is easier to obtain access to the necessary computer hardware and software in a corporate business environ- ment. It can be difficult, however, to allocate enough time within the busy workday to complete a self-study program. Most of your study time will occur after nor- mal working hours, away from the everyday interrup- tions and pressures of your regular job. ADVICE ON TAKING THE EXAM More extensive tips are found in the Final Review sec- tion titled “Study and Exam Prep Tips,” but keep this advice in mind as you study: 02 002-8 Intro 3/1/99 7:46 AM Page 10 [...]... security (7 0-1 75 and 7 0-1 76) The logical design that you derive from the conceptual design will have consequences for the final product The logical design affects many of the desired qualities of a good software solution, such as those listed in this objective Design Visual Basic components to access data from a database in a multitier application (7 0-1 75 and 7 0-1 76) Multitier applications break the various... the rest of the EAM It provides this glue in two ways: á The Development Model is responsible for mediating between the Business Model, on the one hand, and the User, Logical, and Technology Models on the other á The Development Model is also responsible for mediating between the User, Logical, and Technology Models, on the one hand, and the Physical Model on the other Microsoft’s latest Visual Studio... application (7 0-1 75 and 7 0-1 76) The role of the data-access component is central to the n-tier application model In the standard client/server model, the components are divided into the following: á A client component, usually residing on local workstations and containing a user interface and business rules á A server component that implements data access In the standard three-tier model, the components... components and the data-services component á A data-services component that provides data to the dataaccess components In the context of VB6 development, a data-access component will typically be a COM component exposing one or more data-aware classes, as either of the following: 29 04 00 2-8 CH 01 3/1/99 7:38 AM Page 30 30 Pa r t I V IS UAL BAS IC 6 EX AM C O N C E P TS á An ActiveX EXE (an out-of-process... components, their distribution, and their interconnections Although all these models are important (each in its own way) to the overall makeup of the Enterprise Application Model, the most important of these models, and the one you will be mostly concerned with as a VB programmer, is the Development Model The Development Model is important because Microsoft sees it as the pivotal link that holds together the. .. 6. 0 (7 0-1 75) and the Designing and Implementing Desktop Applications with Microsoft Visual Basic 6. 0 (7 0-1 76) certification exams, there are no guarantees Read this book, work through the questions and exercises, and when you feel confident, take the Practice Exam and additional exams using the Top Score test engine This should tell you whether you are ready for the real thing When taking the actual certification... unforeseen uses in the future á If your solution is Web-based and you cannot predict the type of browser that the users will employ, consider using the technology of IIS applications (WebClasses) as described in Chapter 17 Because IIS applications prepare standard Web pages server-side before transmitting them to the client, they are independent of the type of browser used by the client 04 00 2-8 CH 01 3/1/99...02 00 2-8 Intro 3/1/99 7: 46 AM Page 11 á Read all the material Microsoft has been known to include material not expressly specified in the objectives This book has included additional information not reflected in the objectives in an effort to give you the best possible preparation for the examination—and for the real-world network experiences to come á Do the Step by Steps and complete the Exercises... software solution is the component that provides access to the application’s data 1 C H A P T E R Developing the Conceptual and Logical Design and Deriving the Physical Design 04 00 2-8 CH 01 3/1/99 7:38 AM Page 16 OBJECTIVES Design the properties, methods, and events of components (7 0-1 75 and 7 0-1 76) The components that you design in a VB solution will be implemented as objects with their own members... uncertain) the legacy database will be converted to SQL Server Individual users will have state-of -the- art workstations with the fastest available processors and a lot of memory Management anticipates high growth for the system, both because business itself will increase, creating the need for new data-entry personnel, and because users from other departments will begin to use the system as the business . Applications with Microsoft Visual Basic 6. 0 exam (7 0-1 75) and the Designing and Implementing Desktop Applications with Microsoft Visual Basic 6. 0 exam (7 0-1 76) . These exams measure your ability. on Visual Basic 6. These and all the other book features mentioned previ- ously will provide you with thorough preparation for the exam. For more information about the exam or the certifica- tion. Publishing book, call 80 0-4 2 8- 5331. Thank you for selecting MCSD Training Guide: Visual Basic 6 Exams! 02 00 2-8 Intro 3/1/99 7: 46 AM Page 12 I VISUAL BASIC 6 EXAM CONCEPTS 1 Developing the Conceptual