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

Building the project in Classic ASP

The following is a Classic ASP program that reads a CSV file of students and grades and then stores the data in a dictionary with a list of grades for each student. Here’s a breakdown of the code:

  1. The code starts with <% and ends with %>, which indicates that it is embedded within an ASP code block.
  2. The fso, inputFile, studentGrades, line, fields, studentName, grade, grades, and gradeList variables are declared using the Dim statement to hold various data during processing.
  3. The Server.CreateObject method creates an instance of the Scripting.FileSystemObject and Scripting.Dictionary objects (fso and studentGrades).
  4. The Server.MapPath method is used to get the physical path of the students.csv file relative to the server’s filesystem.
  5. The OpenTextFile method of the fso object is called to open the students.csv file for reading.
  6. A loop is initiated using the Do Until statement to read each line from the...