Introduction to Visual Basics (Online)
Visual Basic is the most widely used programming language for creating Windows applications. Why? Because it's easy to learn, and doesn't require you to memorize difficult commands like other programming languages. In this course, you'll learn how to write Windows applications and programs using the Visual Basic programming language and the Visual Basic development environment.
Creating a Windows application ordinarily requires you to write lengthy and complex code. But, as you'll see, the Visual Basic development environment relieves you of this task. Instead, it enables you to create the application program and its components literally with the click of a button or menu item. It even writes all of the necessary code to get the application started for you, which you can then view and fine-tune.
Over the course of 12 lessons, you'll learn the building blocks of programming, including using variables to store data, control structures, and loops. You'll find out how to use the large function library built into Visual Basic, including the .NET Framework, as well as how to write and use your own functions. You'll also see how to use Windows' large and varied library of controls and how to access files and handle errors. And since Windows applications are event-driven and everything in Visual Basic is treated as a programmable object, you'll learn about event-driven and object-oriented programming—concepts that are important not just in Visual Basic, but in other programming languages as well.
Getting Started Using Visual Basic
What's the best way to learn Visual Basic programming? Well, you have to write programs, of course! And your first step toward writing your first program is to install Visual Studio. So in our opening lesson, you'll learn how to install Visual Studio on your computer. After that, we'll walk through creating your first Windows application program while we discuss how a Windows application works.
In the first lesson, you were able to create a working Windows application with just a few mouse clicks. In today's lesson, you'll find out what Visual Basic did behind the scenes to help you create that application. You'll also learn about properties, which are characteristics of an object—such as its size and color—and how to change those properties.
Windows applications are all about events, such as the event a user causes just by clicking a button in the application. Today you'll first learn about event procedures. Then you'll get your feet wet in Visual Basic by writing your first code.
So far, we've been focusing on the form, which is perhaps the most important part of a Windows application's graphical user interface (or GUI). However, a form's primary role is to host other controls that enrich the GUI of Windows applications—menus, toolbars, buttons, text boxes, and list boxes. In this lesson, you'll find out how to add controls to your form and how to write code for these controls.
Data Types and Variables
Most computer programs store information, or data. Today you'll learn all about data types, which represent different varieties of data (such as numeric data or text data). Then we'll go over how to store that information in a variable.
Assignment and Arithmetic Operators
As a former professional chess player, I've marveled at the ability of some computers to play world champion chess players on even terms. But once you understand that computers can calculate far more quickly and accurately than people can, it's easy to see how they're able to outplay the best players. In this lesson, you'll discover how to harness the computer's calculating ability using arithmetic operators.
Relational and Logical Operators
As your programs become more sophisticated, they'll often branch in two or more directions based on whether a condition is true or false. For example, a calculator first needs to determine whether the user chose addition, subtraction, multiplication, or division before performing the indicated arithmetic. Today you'll see how to use comparison and logical operators to determine a user's choice.
Picking up where Lesson 7 left off, once you know the user's choice, you'll want to execute different code based on that choice. In this lesson, you'll learn how to use If and Select Case statements to execute alternative code statements.
Loops and Arrays
When you were a child, your parents may have told you not to repeat yourself. But sometimes your code needs to repeat itself. For example, if your application's users enter invalid data, your code may continue to ask whether they want to retry or quit until they either enter valid data or quit. Today we'll explore how to use loops, which repeat code execution until a condition is no longer true. Then we'll delve into arrays, which may hold multiple values at one time and work very well with loops.
Subroutines and Functions
Many textbooks are several hundred pages long. Imagine how much harder a textbook would be to understand if it consisted of only one very long chapter, rather than being divided into manageable sections. Thankfully, chapters organize books into manageable chunks of information. In today's lesson, you'll learn how to similarly divide up your code into separate procedures. We'll explore two types of procedures—subroutines and functions—that help you organize your code.
When I finish writing something for the evening, I close my word-processing program, and I might even shut down my computer. Of course, the next evening I don't have to start over. What I wrote the previous evening is preserved. However, up until now, our programs haven't saved data so that it's available even after the application exits. Today we'll discuss how to write code that reads from and writes to a text file in order to preserve the data. You'll also learn how to add Open and Save dialog boxes, such as those used in sophisticated programs like Microsoft Word, so you can open a text file to read from it and save to a text file to write to it.
Nobody's perfect, right? Well, your applications won't always run perfectly either. Sometimes they'll stop due to a runtime error, also called an exception. In our final lesson, you'll find out how to prevent and handle exceptions.