PROGRAMMING IN BASIC
CHAPTER 21.   THE HELP MENU

              S   U   B   T   I   T   L   E   S   :  
              21.1 INDEX COMMAND
              21.2 CONTENTS COMMAND
              21.3 TOPIC COMMAND
              21.4 HELP ON HELP COMMAND

CHOOSING COMMANDS ON THE HELP MENU IS ONE WAY TO ACCESS QBASIC'S ON-LINE HELP. (FOR INFORMATION ON OTHER METHODS OF ACCESSING ON-LINE HELP, SEE SECTION 10.8, "USING HELP").

THE HELP MENU CONTAINS THE FOLLOWING COMMANDS:

INDEX.–   DISPLAYS AN ALPHABETICAL LIST OF QBASIC KEYWORDS AND A BRIEF DESCRIPTION OF EACH.
CONTENTS.–   DISPLAYS A VISUAL OUTLINE OF THE ON-LINE HELP CONTENTS.
TOPIC.–   PROVIDES SYNTAX AND USAGE INFORMATION ON SPECIFIC VARIABLES AND QBASIC KEYWORDS.
HELP ON HELP.–   DESCRIBES HOW TO USE ON-LINE HELP AND COMMON KEYBOARD SHORTCUTS.

( TOP ) 21.1 INDEX COMMAND ( TOP )

THE INDEX COMMAND DISPLAYS AN ALPHABETICAL LIST OF THE QBASIC KEYWORDS. TO RECEIVE INFORMATION ON A PARTICULAR KEYWORD, MOVE THE CURSOR TO THE LINE CONTAINING THAT KEYWORD AND PRESS F1. QBASIC DISPLAYS THE HELP WINDOW FOR THAT KEYWORD.

YOU CAN SCROLL THROUGH THE KEYWORD LIST OR JUMP DIRECTLY TO A SPECIFIC LETTER IN THE LIST. FOR EXAMPLE, IF YOU TYPE G, QBASIC MOVES THE CURSOR TO GET, THE FIRST KEYWORD BEGINNING WITH THE LETTER "G." SEE FIGURE 21.1.

( TOP ) 21.2 CONTENTS COMMAND ( TOP )

THE CONTENTS COMMAND DISPLAYS A TABLE OF CONTENTS FOR ON-LINE HELP. IT PROVIDES HINTS ON USING THE QBASIC ENVIRONMENT AND THE QBASIC LANGUAGE, ALONG WITH USEFUL TABLES. FROM HERE YOU CAN TRANSFER TO THE SUBJECT THAT INTERESTS YOU. SEE FIGURE 21.2.

FIGURE 21.2 TABLE OF CONTENTS FOR HELP

FOR DETAILED INFORMATION ON A PARTICULAR TOPIC, PLACE YOUR CURSOR ON THE TOPIC AND PRESS F1. QBASIC DISPLAYS ON-LINE HELP ON THAT TOPIC.

FOR EXAMPLE, THE TABLE OF CONTENTS WINDOW SHOWS SEVERAL ENTRIES UNDER "USING QBASIC." IF YOU MOVE THE CURSOR TO "EDITING KEYS" AND PRESS F1, A SCREEN APPEARS WITH THE MOST FREQUENTLY USED EDITING SHORTCUT KEYS.

( TOP ) 21.3 TOPIC COMMAND ( TOP )

THE TOPIC COMMAND PROVIDES SPECIFIC INFORMATION ON THE SYNTAX AND USAGE OF THE QBASIC VARIABLE, SYMBOL, KEYWORD, MENU, COMMAND, OR DIALOG BOX AT OR CONTAINING THE CURSOR. WHEN THE TOPIC COMMAND IS ACTIVE, THE SUBJECT ON WHICH IT WILL PROVIDE ON-LINE HELP APPEARS AFTER THE WORD TOPIC.

CHOOSING THE TOPIC COMMAND IS THE SAME AS PRESSING F1. YOU CAN GET HELP ON ANY KEYWORD OR VARIABLE AT ANY TIME BY TYPING THE WORD OR NAME AND IMMEDIATELY CHOOSING THE TOPIC COMMAND.

IF YOU CHOOSE THE TOPIC COMMAND WHENEVER YOU ENCOUNTER A SYNTAX ERROR, YOU CAN IMMEDIATELY CORRECT THE USAGE OF YOUR STATEMENT. FOR EXAMPLE, SUPPOSE YOU ENTER THE LINE BELOW, WHICH IS MISSING THE WORD TO AND INSTEAD CONTAINS A COMMA:

FOR I% = 1,10

QBASIC FLAGS THE SYNTAX ERROR WITH THE MESSAGE EXPECTED:
"PRESS F1 OR THE HELP BUTTON FOR HELP ON THE ERROR ITSELF".
FOR INFORMATION ON THE KEYWORD FOR, MOVE THE CURSOR TO THE FOR STATEMENT AND CHOOSE THE TOPIC COMMAND. QBASIC KEEPS YOUR PROGRAM CODE VISIBLE AT THE BOTTOM OF THE SCREEN. SEE FIGURE 21.3.

FIGURE 21.3 HELP ON THE FOR...NEXT STATEMENT

TO COPY SAMPLE CODE FROM THE FOR HELP SCREEN INTO YOUR PROGRAM, DO THE FOLLOWING:

1.–   CHOOSE THE EXAMPLE HYPERLINK AT THE TOP OF THE WINDOW.
2.–   SELECT THE EXAMPLE CODE AND CHOOSE COPY FROM THE EDIT MENU.
3.–   PRESS ESC TO CLOSE THE HELP WINDOW.
4.–   MOVE THE CURSOR TO THE PLACE IN YOUR PROGRAM YOU WANT THE TEXT TO APPEAR, AND CHOOSE PASTE FROM THE EDIT MENU.

YOU CAN CUSTOMIZE THE PASTED CODE OR USE IT AS IT IS.
SHORTCUT KEY:   F1

( TOP ) 21.4 HELP ON HELP COMMAND ( TOP )

THE HELP ON HELP COMMAND DESCRIBES HOW TO USE THE QBASIC ON-LINE HELP SYSTEM. THE HELP ON HELP SCREEN GIVES A DESCRIPTION OF THE MAIN HELP FEATURES. FOR MORE SPECIFIC INFORMATION, PRESS ESC TO EXIT HELP ON HELP, AND USE THE TOPIC COMMAND ON THE HELP MENU OR PRESS F1.

FIGURE 21.4 HELP ON HELP SCREEN

SHORTCUT KEY:   SHIFT+F1.

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