Book Image

Visual Basic Quickstart Guide

By : Aspen Olmsted
Book Image

Visual Basic Quickstart Guide

By: Aspen Olmsted

Overview of this book

Whether you’re an absolute beginner or an experienced developer looking to learn the Visual Basic language, this book takes a hands-on approach to guide you through the process. From the very first chapters, you'll delve into writing programs, exploring core concepts such as data types, decision branching, and iteration. Additionally, you’ll get to grips with working with data structures, file I/O, and essential object-oriented principles like inheritance and polymorphism. This book goes beyond the basics to equip you with the skills to read and write code across the entire VB family, spanning VB Script, VBA, VB Classic, and VB.NET, enabling you to handle legacy code maintenance with ease. With clear explanations, practical examples, and hands-on exercises, this book empowers you to tackle real-world software development tasks, whether you're enhancing existing projects or embarking on new ones. It addresses common challenges like distinguishing between the variations of the VB programming language to help you choose the right one for your projects. Don't let VB's extensive legacy daunt you; embrace it with this comprehensive guide that equips you with practical, up-to-date coding skills to overcome the challenges presented by Visual Basic's rich history of over two decades.
Table of Contents (27 chapters)
Free Chapter
1
Part 1:Visual Basic Programming and Scripting
9
Part 2:Visual Basic Files and Data Structures
14
Part 3:Object-Oriented Visual Basic
20
Part 4:Server-Side Development

Modularizing code in functions

VB provides hundreds of built-in functions. These functions can be used to perform standard calculations, manipulate strings and arrays, and interact with the user interface of a program. These out-of-the-box functions are basically code-written and tested for you to reuse. Here are some commonly used functions in VB:

  • Abs: Returns the absolute value of a number without its sign.
  • Date: Returns the current date while a program is running.
  • Cint: Converts a parameter to an integer.
  • Format: Formats a numeric or date value as a string.
  • InStr: Returns the position of the first occurrence of a substring in a string. This is similar to the find functionality in word processing software.
  • Int: Returns the integer portion of a number.
  • Lcase: Converts a string to lowercase.
  • Left: Extracts a specified number of characters from the beginning of a string. This is similar to the Mid function but only works from the left side of the...