Fundamentals Overview IDE (Editor) Syntax Variables Data Types Declarations Scope Operators

Standard Functions Arithmetic Trigonometry Strings Arrays Date/Time Flow Control Procedures Printing Files Folders

Additional Capabilities Keyboard Sound Graphics Concepts Screen (text) Screen (drawing) Gaming (sprites) Event Trapping Errors System Calls

QBasic IDE (Editor)
The QBasic Integrated Development Editor (IDE) is very simple editor, but does contain enough capability to support creating programs of any size.

The startup screens for QBasic as shown below. For more information on the menu options, click on one of the following links.

File	View	Run	Options
Edit	Search	Debug	Help

For it's time, the menu option above were considered reasonably complete. However, today's language IDE's are considerably more complex.

Summary of Screens
QBasic has 4 views, or windows, in which to view information.

• Program - Displays the main source code, or that of a single procedure (sub/function). The filename of the program or the name of the procedure is displayed at the top of the window.

• Immediate - Lines of code which are executed one at a time (whenever Enter is pressed). The word "Immediate" is displayed at the top of this window.

• Help Window - Discussion on QBasic topics. Note that pressing F1 while the cursor is in a Program window opens the Help file to the topic under the cursor. The word "Help" and the current Help topic is displayed at the top of this window.

• Output - The output of the program, displayed within the QBasic window. Before a program is run this windows is blank. once a window is run the output stays in the window unless a CLS command is executed. This screen is blank when QBasic starts up, but when a program is run this window displays "Press any key to continue".

Startup Screen
When started, the following window is presented. Press ESC to clear the screen and make QBasic ready for input.

Empty Screen
Once ESC is pressed, this is the window that is displayed, ready for text entry or loading of a previously saved QBasic source code file.

This opening screen is where the program statements are typed.

TIP: When you type in statements I suggest using lower case characters. Once you press enter, QBasic IDE will capitalize any keywords it finds on the line. This is a good, visual way to make sure you've used valid statements. If a word isn't capitalized that you expected to be capitalized, then you'll be alerted to look at it for an error in typing!

TIP: If you place the cursor over something you've typed in and press F1, QBasic will attempt to find the word in its Help file. If QBasic finds the word, it will open Help to the entry for that word.

TIP: You can use the menu to start a program, but F5 will do the same thing.

TIP: To stop a program that is running, press CTRL-Break.

Triple Window
This is the QBasic screen, with the Program, Immediate, and Help windows all visible. The size of each window can be adjusted using the mouse.

Output Window
This is the QBasic screen, the output of an executed program showing. In this case, this is the result of the CLS command (the output screen cleared).

Status Line
At the bottom of all windows is the QBasic status line. It lists several common commands that are available, depending on which of the above windows are selected.

The status bar also provides a description of highlighted menu options. To highlight sub-menus, use the arrow keys.

The status of the Caps Lock and Num Lock keys,as well as current line and column under the cursor are also shown.

If you have any suggestions or questions, please let me know.