Computer languages can be described as having a low-visual or a high-visual orientation. Prior to 1990, most languages were low-visual languages, so programmers had considerable difficulty designing the computer forms and reports, data entry screens, and navigation tools by which to move from one area of a computer program to another. High-visual languages greatly simplify the tasks of designing forms, screens, and navigation tools. For this and other reasons, Visual Basic is known as a rapid prototyping language. Its design tools let you quickly design a version or prototype of a computer application.
Low-Visual Languages
Let’s consider how a low-visual language differs from a high-visual language. Low-visual languages are not supported by a GUI. Instead, the programmer usually works with a blank terminal screen, adding line after line of instruction to that screen. After the instructions are entered, the programmer issues a Run or Execute command to execute the instructions. Only at this time do visual images appear on the screen. Those of you who use common DOS-level commands, such as Copy, Del or CD use a low-visual language.High-Visual Languages
High-visual languages are supported by a GUI design environment. The appearance of the design environment is conceived to improve speed in program design and can even be customized to suit your needs. At the top of the screen is a menu bar, which contains the File, Edit, View, Project, Format, Debug Run, Tools, Add-Ins, Window and Help menus. Below the menu bar is a toolbar.
The buttons appearing on the toolbar allow quick access to the most commonly used commands. As you work through the exercises you will become familiar with the use of each tool in the toolbox. Finally, the Visual Basic startup screen often contains a Form Window, a Project (Explorer) Window and a Properties Window. “Writing and Running Your First Visual Basic Program,” asks you to use each in constructing a Visual Basic Program.
Pause and Breathe for a Moment!
Looking at the toolbar and toolbox the first time might fill your heart with fear. You might exclaim, I can’t remember what all those icons mean! With Visual Basic, help is readily on hand. To quickly identify a control, just let your mouse pointer linger over an item in the toolbox. A ToolTip appears by your pointer and identifies the control. The same applies for buttons on the toolbar. You can also click the button you want to inspect and press the Help key: the F1 function key on the keyboard. The Visual Basic Help screen appears with a description of the button.
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