Beginning Visual Basic 2015

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3 Beginning Visual Basic 2015 Introduction xxvii Chapter 1 Welcome to Visual Basic Chapter 2 The Microsoft.NET Framework Chapter 3 Writing Software Chapter 4 Controlling the Flow Chapter 5 Working with Data Structures Chapter 6 Building Windows Applications Chapter 7 Displaying Dialogs Chapter 8 Creating Menus Chapter 9 Debugging and Error Handling Chapter 10 Building Objects Chapter 11 Advanced Object-Oriented Techniques Chapter 12 Accessing Data Using Structured Query Language Chapter 13 Database Programming with SQL Server and ADO.NET Chapter 14 ASP.NET Chapter 15 Deploying Your Application Chapter 16 Windows 8 Apps Appendix Exercise Solutions Index

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5 Beginning Visual Basic 2015

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7 Beginning Visual Basic 2015 Bryan Newsome

8 Beginning Visual Basic 2015 Published by John Wiley & Sons, Inc Crosspoint Boulevard Indianapolis, IN Copyright 2016 by John Wiley & Sons, Inc., Indianapolis, Indiana Published simultaneously in Canada ISBN: ISBN: (ebk) ISBN: (ebk) Manufactured in the United States of America No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) , fax (978) Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) , fax (201) , or online at Limit of Liability/Disclaimer of Warranty: The publisher and the author make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation warranties of fitness for a particular purpose. No warranty may be created or extended by sales or promotional materials. The advice and strategies contained herein may not be suitable for every situation. This work is sold with the understanding that the publisher is not engaged in rendering legal, accounting, or other professional services. If professional assistance is required, the services of a competent professional person should be sought. Neither the publisher nor the author shall be liable for damages arising herefrom. The fact that an organization or Web site is referred to in this work as a citation and/or a potential source of further information does not mean that the author or the publisher endorses the information the organization or Web site may provide or recommendations it may make. Further, readers should be aware that Internet Web sites listed in this work may have changed or disappeared between when this work was written and when it is read. For general information on our other products and services please contact our Customer Care Department within the United States at (877) , outside the United States at (317) or fax (317) Wiley publishes in a variety of print and electronic formats and by print-on-demand. Some material included with standard print versions of this book may not be included in e-books or in print-on-demand. If this book refers to media such as a CD or DVD that is not included in the version you purchased, you may download this material at For more information about Wiley products, visit Library of Congress Control Number: Trademarks: Wiley, the Wiley logo, Wrox, the Wrox logo, Programmer to Programmer, and related trade dress are trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates, in the United States and other countries, and may not be used without written permission. Visual Basic is a registered trademark of Microsoft Corporation. All other trademarks are the property of their respective owners. John Wiley & Sons, Inc., is not associated with any product or vendor mentioned in this book.

9 For my girls, Jennifer and Katelyn.

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11 About the Author Bryan Newsome leads a team of top developers specializing in Microsoft solutions. Since starting building Visual Basic 5 solutions, he has embraced each new version of Visual Basic and now creates all new solutions leveraging the.net platform and VB.NET. He provides clients with solutions and mentoring on leading-edge Microsoft technologies. For VB.NET, Bryan is a Microsoft Certified Application Developer.

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13 About the Technical Editor Valan Money is a Microsoft Certified Solution Developer for Web and Windows applications. He has been using Visual Basic since 1996 and got his first certification in Visual Basic 4.0. Since then, he has also received certifications in newer versions of VB and VB.NET. He works as Technical Team Lead and Senior Consultant for projects using Microsoft technologies. He holds a Masters degree in Computer Science from St. Joseph s College, Tiruchirappalli, India.

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15 Credits Senior Acquisitions Editor Kenyon Brown Project Editor Maureen S. Tullis Technical Editor Valan Money Production Editor Dassi Zeidel Copy Editor Scott D. Tullis Manager of Content Development & Assembly Mary Beth Wakefield Marketing Director David Mayhew Marketing Manager Carrie Sherrill Professional Technology & Strategy Director Barry Pruett Business Manager Amy Knies Associate Publisher Jim Minatel Project Coordinator, Cover Brent Savage Proofreader Nancy Carrasco Indexer Johnna VanHoose Dinse Cover Designer Wiley Cover Image anasimin/istockphoto

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17 Acknowledgments Thanks to those who worked so hard to get this book on the shelves at Wiley and Wrox. Special thanks (again) to Maureen Tullis who went above and beyond to help me finish mostly on schedule.

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19 Contents Introduction xxvii Chapter 1: Welcome to Visual Basic Implementing Event-Driven Programming 2 Installing Visual Basic The Visual Studio 2015 IDE 5 The Profile Setup Page 5 The Menu 6 The Toolbars 8 Creating a Simple Application 9 Windows in the Visual Studio 2015 IDE 10 Modified Hungarian Notation 17 The Code Editor 18 Using the Help System 22 Summary 23 Chapter 2: The Microsoft.NET Framework 25 The.NET Vision 25 This Sounds Like Java 26 Where Now? 27 Writing Software for Windows 27 The.NET Framework Classes 28 Executing Code 30 Common Language Runtime 31 Code Loading and Execution 31 Application Isolation 31 Security 32 Interoperability 33 Exception Handling 33 The Common Type System and Common Language Specification 33 Summary 34 Chapter 3: Writing Software 37 Information and Data 37 Algorithms 38

20 Contents What Is a Programming Language? 39 Working with Variables 40 Comments and Whitespace 43 Comments 43 Whitespace 45 Data Types 45 Working with Numbers 45 Common Integer Math Operations 46 Integer Math Shorthand 49 The Problem with Integer Math 50 Floating-Point Math 50 Working with Strings 53 Using Dates 62 Boolean 69 Storing Variables 69 Binary 69 Bits and Bytes 70 Representing Values 70 Converting Values 72 Methods 74 Why Use Methods? 74 Methods You ve Already Seen 75 Building a Method 78 Choosing Method Names 81 Scope 82 Summary 84 Chapter 4: Controlling the Flow 87 Making Decisions 87 The If Statement 88 The Else Statement 90 Allowing Multiple Alternatives with ElseIf 90 Nested If Statements 92 Single-Line If Statement 92 Comparison Operators 92 String Comparison 101 Select Case 102 Case-Insensitive Select Case 106 Multiple Selections 108 The Case Else Statement 109 Different Data Types with Select Case 110 xviii

21 contents Loops 110 The For...Next Loop 110 The Do...Loop Loops 116 Nested Loops 120 Quitting Early 121 Quitting Do...Loops 123 Infinite Loops 124 Summary 125 Chapter 5: Working with Data Structures 127 Understanding Arrays 128 Defining and Using Arrays 128 Using For Each...Next 131 Passing Arrays as Parameters 133 Sorting Arrays 136 Going Backward 137 Initializing Arrays with Values 138 Understanding Enumerations 139 Using Enumerations 140 Determining the State 143 Setting Invalid Values 146 Understanding Constants 146 Using Constants 146 Different Constant Types 148 Structures 148 Building Structures 149 Adding Properties to Structures 152 Working with ArrayLists 153 Using an ArrayList 153 Deleting from an ArrayList 158 Showing Items in the ArrayList 161 Working with Collections 162 Creating CustomerCollection 163 Adding an Item Property 164 Building Lookup Tables with Hashtable 166 Using Hashtables 166 Cleaning Up: Remove, RemoveAt, and Clear 169 Case Sensitivity 172 Advanced Array Manipulation 173 Dynamic Arrays 173 Using Preserve 175 Summary 176 xix

22 Contents Chapter 6: Building Windows Applications 179 Responding to Events 180 Counting Characters 184 Counting Words 188 Creating More Complex Applications 191 Creating the Toolbar 192 Creating the Status Bar 195 Creating an Edit Box 196 Clearing the Edit Box 197 Responding to Toolbar Buttons 199 Using Multiple Forms 202 About Dialog 202 Summary 206 Chapter 7: Displaying Dialogs 209 The MessageBox 210 Available Icons for MessageBox 210 Available Buttons for MessageBox 211 Setting the Default Button 211 Miscellaneous Options 212 The Show Method Syntax 212 Example Message Boxes 214 The OpenFileDialog Control 218 The OpenFileDialog Control 218 The Properties of OpenFileDialog 218 OpenFileDialog Methods 220 Using the OpenFileDialog Control 221 The SaveDialog Control 226 The Properties of SaveFileDialog 226 SaveFileDialog Methods 227 Using the SaveFileDialog Control 227 The FontDialog Control 231 The Properties of FontDialog 231 The Methods of FontDialog 232 Using the FontDialog Control 232 The ColorDialog Control 235 The Properties of ColorDialog 236 Using the ColorDialog Control 237 The PrintDialog Control 238 The Properties of PrintDialog 239 xx

23 contents Using the PrintDialog Control 240 The PrintDocument Class 240 The Properties of the PrintDocument Class 240 Printing a Document 241 The FolderBrowserDialog Control 248 The Properties of FolderBrowserDialog 248 Using the FolderBrowserDialog Control 249 Summary 252 Chapter 8: Creating Menus 255 Understanding Menu Features 255 Images 256 Access Keys 256 Shortcut Keys 256 Check Marks 256 The Properties Window 257 Creating Menus 259 Designing the Menus 259 Adding Toolbars and Controls 261 Coding Menus 263 Coding the View Menu and Toolbars 267 Testing Your Code 269 Context Menus 272 Creating Context Menus 272 Enabling and Disabling Menu Items and Toolbar Buttons 275 Summary 279 Chapter 9: Debugging and Error Handling 283 Major Error Types 284 Syntax Errors 284 Execution Errors 288 Logic Errors 288 Debugging 289 Creating a Sample Project 289 Setting Breakpoints 306 Debugging Using the Watch Window and QuickWatch Dialog Box 313 Debugging with the Autos Window 316 Debugging with the Locals Window 316 Error Handling 318 Using Structured Error Handling 319 Summary 321 xxi

24 Contents Chapter 10: Building Objects 325 Understanding Objects 326 Encapsulation 327 Methods and Properties 327 Events 328 Visibility 328 What Is a Class? 329 Building Classes 330 Reusability 330 Designing an Object 332 State 332 Behavior 333 Storing State 333 Real Properties 336 Read/Write Properties 339 Auto-Implemented Properties 342 The IsMoving Method 343 Constructors 345 Inheritance 346 Adding New Methods and Properties 348 Adding a GetPowerToWeightRatio Method 350 Changing Defaults 352 Polymorphism: Scary Word, Simple Concept 354 Overriding More Methods 354 Inheriting from the Object Class 356 Objects and Structures 357 The Framework Classes 357 Namespaces 358 The Imports Statement 360 Creating Your Own Namespace 361 Inheritance in the.net Framework 364 Summary 365 Chapter 11: Advanced Object-Oriented Techniques 367 Building a Favorites Viewer 368 Internet Shortcuts and Favorites 368 Using Classes 371 Scanning Favorites 377 Viewing Favorites 384 An Alternative Favorite Viewer 386 xxii

25 contents Building a Favorites Tray 387 Displaying Favorites 388 Using Shared Properties and Methods 392 Using Shared Properties 392 Using Shared Methods 397 Understanding Object-Oriented Programming and Memory Management 398 Garbage Collection 400 Releasing Resources 400 Defragmentation and Compaction 401 Summary 402 Chapter 12: Accessing Data Using Structured Query Language 405 What You Need to Complete This Chapter s Exercises 406 What Is a Database? 407 Database Tables 407 Primary and Foreign Keys 413 Queries 415 Understanding Basic SQL Syntax 415 Using SELECT Statement 416 Using the JOIN Statement 417 Using the UPDATE Statement 419 Using the DELETE Statement 419 Using the INSERT Statement 420 Using the SQL Comment 421 Executing Queries in SQL Server 421 Summary 425 Chapter 13: Database Programming with SQL Server and ADO.NET 427 ADO.NET 428 ADO.NET Data Namespaces 428 The SqlConnection Class 429 Working with the Connection String Parameters 430 Opening and Closing the Connection 431 The SqlCommand Class 431 The SqlDataAdapter Class 434 The DataSet Class 438 DataView 438 The ADO.NET Classes in Action 440 xxiii

26 Contents Data Binding 450 BindingContext and CurrencyManager 450 Binding Controls 451 Binding Examples 452 Summary 480 Chapter 14: ASP.NET 483 Thin Client Architecture 484 Web Forms versus Windows Forms 485 Windows Forms Advantages 485 Web Forms Advantages 485 Web Applications: The Basic Pieces 486 Web Servers 486 Browsers 486 HyperText Markup Language 487 JavaScript 487 Cascading Style Sheets 487 Active Server Pages 488 Benefits of ASP.NET Web Pages 488 Special Website Files 488 Development 489 Controls: The Toolbox 489 Building Websites 490 Creating a Web Form for Client and Server Side Processing 490 Website Locations with VS Performing Data Entry and Validation 498 Using the GridView to Build a Data Driven Web Form 507 Summary 512 Chapter 15: Deploying Your Application 515 What Is Deployment? 516 ClickOnce Deployment 516 XCOPY Deployment 521 Visual Studio 2015 Setup Application Options 522 Deploying Different Solutions 522 Private Assemblies 523 Shared Assemblies 523 Deploying Desktop Applications 524 Deploying Web Applications 524 xxiv

27 contents Deploying XML Web Services 524 Useful Tools 525 Summary 525 Chapter 16: Windows 8 Apps 529 Windows 8 Application Design Principles 530 Using Touch 530 Application Commands 531 Windows 8 Controls 532 Coding Windows 8 Apps with XAML 533 Creating Your First Windows 8 App 534 Application Layout 548 Application Views 548 Screen Sizes and Orientation 548 Summary 553 Appendix: Exercise Solutions 557 Index 569 xxv

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29 Introduction Visual Basic 2015 is Microsoft s latest version of the highly popular Visual Basic.NET programming language, one of the many languages supported in Visual Studio Visual Basic 2015 s strength lies in its ease of use and the speed at which you can create Windows Forms and Windows 8 applications, web applications, and mobile device applications. In this book, we introduce you to programming with Visual Basic 2015 and show you how to create these types of applications and services. Along the way you ll also learn about object-oriented techniques and learn how to create your own business objects and Windows controls. Microsoft s.net Framework provides Visual Basic 2015 programmers with the capability to create full object-oriented programs, just like the ones created using C# or C++. The.NET Framework provides a set of base classes that are common to all programming languages in Visual Studio 2015, which provides you with the same capability to create object-oriented programs as a programmer using C# or C++. This book will give you a thorough grounding in the basics of programming using Visual Basic 2015; from there the world is your oyster. Who This Book Is For This book is designed to teach you how to write useful programs in Visual Basic 2015 as quickly and easily as possible. There are two kinds of beginners for whom this book is ideal: You re a beginner to programming and you ve chosen Visual Basic 2015 as the place to start. That s a great choice! Visual Basic 2015 is not only easy to learn, it s also fun to use and very powerful. You can program in another language but you re a beginner to.net programming. Again, you ve made a great choice! Whether you ve come from Fortran or Cobol, you ll find that this book quickly gets you up to speed on what you need to know to get the most from Visual Basic What This Book Covers Visual Basic 2015 offers a great deal of functionality in both tools and language. No one book could ever cover Visual Basic 2015 in its entirety you would need a library of books. What this book aims to do is to get you started as quickly and easily as possible. It shows you the roadmap, so to speak, of what there is and where to go. Once we ve taught you the basics of creating working applications (creating the windows and controls, how your code should handle unexpected events, what

30 introduction object-oriented programming is, how to use it in your applications, and so on) we ll show you some of the areas you might want to try your hand at next: Chapters 1 through 8 provide an introduction to Visual Studio 2015 and Windows programming. Chapter 9 provides an introduction to application debugging and error handling. Chapter 10 provides an introduction to object-oriented programming and building objects. Chapter 11 provides an introduction to creating Windows Forms user controls. Chapters 12 and 13 provide an introduction to programming with databases and covers Structured Query Language, SQL Server, and ADO.NET. Chapter 14 provides an introduction to ASP.NET and shows you how to write applications for the web. Chapter 15 introduces you to deploying applications using ClickOnce technology. Chapter 16 show you how to build your first Windows 8 application and introduces you to design principles for touch interfaces. What You Need to Use This Book Apart from a willingness to learn, all you ll need are a PC running Windows 8 (preferred), Windows 7, Windows Server 2008 R2, Windows Server 2015; Internet Explorer; and of course: Microsoft Visual Basic 2015Community Edition or higher For the database chapters, you should install SQL Server 2014 Express, although, any edition you have should work with little to no changes required. Conventions To help you get the most from the text and keep track of what s happening, we ve used a number of conventions throughout the book. Try It Out The Try It Out is an exercise you should work through, following the text in the book. 1. They usually consist of a set of steps. 2. Each step has a number. 3. Follow the steps through with your copy of the database. How It Works After each Try It Out, the code you ve typed will be explained in detail. xxviii