ABS(numeric-expression)
The absolute value function returns the unsigned magnitude of its
argument. For example, ABS(-1) and ABS(1) are both 1.
■ Example
ASC(stringexpression)
If stringexpression is null, ASC produces a run-time error message
(Illegal function call).
■ See Also
ATN(numeric-expression)
The numeric-expression can be of any numeric type.
The result is given in radians and is in the range -π/2 to π/2 radians,
where π=3.141593. ATN is evaluated by default in single precision unless
BEEP
The BEEP statement makes a sound through the loudspeaker. This statement
makes the same sound as the following statement:
PRINT CHR$(7)
CALL name«( argumentlist )» name« argumentlist »
The CALL statement takes the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
CDBL(numeric-expression)
The numeric-expression may be any numeric expression. This function has
the same effect as assigning the numeric expression to a double-precision
variable.
CHR$(code)
CHR$ is commonly used to send a special character to the screen or
printer. For example, you can send a form feed (CHR$(12)) to clear the
screen and return the cursor to the home position.
CINT(numeric-expression)
If numeric-expression is not in the range -32,768 to 32,767, the function
produces a run-time error message that reads Overflow.
CINT differs from the FIX and INT functions, which truncate, rather than
CLNG(numeric-expression)
If numeric-expression is not in the range -2,147,483,648 to 2,147,483,647,
the function produces an error message that reads Overflow.
■ Example
CLS «{0 | 1 | 2}» There are several ways to use the CLS statement, as described in the
following list:
Statement Description
CONST constantname = expression «,constantname = expression»...
Argument Description
──────────────────────────────────────────────────────────────────────────
constantname A name following the same rules as a BASIC
variable name. You may add to the name a
COS(numeric-expression)
The expression, numeric-expression, can be any numeric type.
By default, the cosine is calculated in single precision. If
numeric-expression is a double-precision value, the cosine is calculated
CSNG(numeric-expression)
The CSNG function has the same effect as assigning the numeric-expression
to a single-precision variable.
CSNG rounds the value, if necessary, before converting it.
CSRLIN
To return the current column position, use the POS function. ■ See Also
DATA constant1 «,constant2»...
The constant1, constant2, and so on in a DATA statement can be any valid
numeric or string constant.
Names of symbolic constants (defined in a CONST statement) appearing in
DATE$
The DATE$ function returns a ten-character string in the form mm-dd-yyyy,
where mm is the month (01-12), dd is the day (01-31), and yyyy is the year
(1980-2099).
Parsed but ignored
DECLARE {FUNCTION | SUB } name «(«parameterlist»)» The DECLARE statement uses the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
DEFINT letterrange «,letterrange»... DEFSNG letterrange «,letterrange»... DEFDBL letterrange «,letterrange»... DEFLNG letterrange «,letterrange»...
The letterrange has the form:
letter1«-letter2»
DIM «SHARED» variable«(subscripts)»«AS type»«,variable«(subscripts)»«AStype
The following list describes the parts of the DIM statement:
Part Description
──────────────────────────────────────────────────────────────────────────
DO «statementblock » LOOP «{WHILE | UNTIL} booleanexpression»
DO «{WHILE | UNTIL} booleanexpression» «statementblock » LOOP The following list describes the arguments of the DO...LOOP statement:
Argument Description
──────────────────────────────────────────────────────────────────────────
END «{DEF | FUNCTION | IF | SELECT | SUB | TYPE}» There are several ways to use the END statement, as described in the
following list:
Statement Description
EXIT {DEF | DO | FOR | FUNCTION | SUB } There are several ways to use the EXIT statement as described in the
following list:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
EXP(x)
The EXP function returns e (the base of natural logarithms) to the power
of x. The exponent x must be less than or equal to 88.02969. A value of x
greater than 88.02969 produces an Overflow error message.
FIX(x)
The x is a numeric expression. FIX(x) is equivalent to SGN(x)*INT(ABS(x)).
The difference between FIX and INT is that for negative x, FIX returns the
first negative integer greater than x, while INT returns the first
negative integer less than x.
FOR counter = start TO end «STEP increment» . . .
The FOR statement takes the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
FUNCTION name «(parameterlist)»«STATIC» . . .
The following list describes the parts of the FUNCTION statement:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Part Description
GOSUB {linelabel1 | linenumber1 }
.
.
.
The GOSUB...RETURN statements take the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
GOTO {linelabel | linenumber} The GOTO statement provides a way to branch unconditionally to another
line (linelabel or linenumber). A GOTO statement can branch only to
another statement at the same level of a program. You cannot use GOTO to
enter or exit a SUB, FUNCTION, or multiline DEF FN function. You can,
HEX$(expression)
The argument expression is rounded to an integer or, if the expression is
outside the integer range, a long integer before the HEX$ function
evaluates it.
IF booleanexpression THEN thenpart «ELSE elsepart» IF booleanexpression1 THEN «statementblock-1» «ELSEIF booleanexpression2 THEN
The single-line form of the statement is best used for short,
straightforward tests where only one action is taken.
The block form provides several advantages:
INSTR(«start,»stringexpression1,stringexpression2)
The following list describes the INSTR function arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
INT(numeric-expression)
The INT function removes the fractional part of its argument. ■ See Also
LBOUND(array«,dimension»)
The LBOUND function is used with the UBOUND function to determine the size
of an array. LBOUND takes the following arguments:
Argument Description
LCASE$ (stringexpression)
The LCASE$ function takes a string variable, string constant, or string
expression as its single argument. LCASE$ works with both variable- and
fixed-length strings.
LEFT$(stringexpression,n)
The argument stringexpression can be any string variable, any string
constant, or any string expression.
The argument n is a numeric expression in the range 0-32,767 indicating
«LET»variable=expression
Notice that the word LET is optional. The equal sign in the statement is
enough to inform QuickBASIC that the statement is an assignment statement.
LET statements can be used with record variables only when both variables
LOG(n)
The numeric expression, n, must be greater than zero. The natural
logarithm is the logarithm to the base e. The constant e is approximately
equal to 2.718282.
LTRIM$(stringexpression)
The stringexpression can be any string expression. ■ See Also
MID$(stringexpression,start«,length»)
The MID$ function takes the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
OCT$(numeric-expression)
The numeric-expression may be of any type. The numeric-expression is
rounded to an integer or long integer before the OCT$ function evaluates
it.
POS(0)
The leftmost cursor position is numbered 1. To return the current
vertical-line position of the cursor, use the CSRLIN function.
■ See Also
PRINT «expressionlist» «{, | ;}» If expressionlist is omitted, a blank line is printed. If expressionlist
is included, the values of the expressions are printed on the screen. The
expressions in the list may be numeric or string expressions. (String
literals must be enclosed in quotation marks.)
READ variablelist
A variablelist is a series of valid BASIC variables separated by commas.
READ statements are always used with DATA statements. READ assigns DATA
values to variables on a one-to-one basis. These variables may be numeric
or string. Attempting to read a string value into a numeric variable
REM remark ' remark
REM statements are not compiled, but they appear exactly as entered when
the program is listed. You may branch from a GOTO or GOSUB statement to a
REM statement. Execution continues with the first executable statement
after the REM statement.
RESTORE «{linenumber | linelabel }» After executing a RESTORE statement without a specified linenumber or
linelabel, the next READ statement gets the first item in the first DATA
statement in the program.
RETURN «{linenumber | linelabel }» Without a line label or number, RETURN continues execution where an event
occurred (for event handling) or at the statement following the GOSUB (for
subroutine calls). GOSUB and RETURN without a line number can be used
anywhere in a program, but the GOSUB and corresponding RETURN must be at
RIGHT$(stringexpression,n)
The argument stringexpression can be any string variable, string constant,
or string expression. If n is equal to the number of characters in the
argument stringexpression, then the RIGHT$ function returns
stringexpression. If n = 0, RIGHT$ returns the null string (length zero).
RTRIM$(stringexpression)
The stringexpression can be any string expression. The RTRIM$ function
works with both fixed- and variable-length string variables.
■ See Also
SELECT CASE testexpression CASE expressionlist1 «statementblock-1» «CASE expressionlist2
The following list describes the parts of the SELECT CASE statement:
Argument Description
──────────────────────────────────────────────────────────────────────────
SGN(numeric-expression)
The SGN function returns a value depending on the sign of its argument:
If numeric-expression > 0, then SGN(numeric-expression) returns 1.
SHARED variable «AS type» «, variable «AS type»»...
The argument variable is either an array name followed by () or a variable
name. The AS clause can be used to indicate the variable's type. The type
argument can be INTEGER, LONG, SINGLE, DOUBLE, STRING, fixed-length string
(STRING*length), or a user-defined type.
SIN(x)
When x is a double-precision value, the SIN function is calculated with
double-precision accuracy. When x is not double precision, SIN is
calculated with single-precision accuracy.
SLEEP « seconds »
The optional argument seconds determines the number of seconds the program
is suspended. The SLEEP statement suspends the program until one of the
following events occurs:
SPACE$(n)
The expression n is rounded to an integer and must be in the range
0-32,767.
■ See Also
SPC(n)
SPC may only be used with PRINT and LPRINT statements. The argument n must
be in the range 0-32,767. A semicolon (;) is assumed to follow the SPC(n)
command.
SQR(n)
The argument n must be >= 0. ■ Example
STATIC variablelist
A STATIC statement variablelist has the following syntax:
variable«( )»«AS type» «, variable«( )»«AS type»»...
STOP
STOP statements can be used anywhere in a program to terminate execution.
When running in the QuickBASIC environment, the STOP statement leaves
files open and does not exit to the operating system. In contrast, a STOP
STR$(numeric-expression)
If numeric-expression is positive, the string returned by the STR$
function contains a leading blank. The VAL function complements STR$.
■ See Also
STRING$(m,n) STRING$(m,stringexpression)
The STRING$ function has the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
SUB globalname«(parameterlist)» «STATIC» . . .
The SUB statement takes the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
SWAP variable1,variable2
Any type of variable can be swapped (integer, long, single precision,
double precision, string, or record). However, the two variables must be
exactly the same type or an error message appears (Type mismatch). For
example, trying to swap an integer with a single-precision value produces
SYSTEM
When a SYSTEM command is executed, all files are closed and BASIC exits to
the operating system (for stand-alone executable programs) or stops
program execution (if the program is run in the QuickBASIC environment).TAB(column)
The argument, column, is a numeric expression that is the column number of
the new print position. If the current print position is already beyond
column, the TAB function moves the print position to that column on the
next line. Column 1 is the leftmost position, and the rightmost position
TAN(x)
TAN is calculated with single-precision accuracy unless x is a
double-precision value, in which case TAN is calculated with
double-precision accuracy.
TIME$
The TIME$ function returns an eight-character string in the pattern
hh:mm:ss, where hh is the hour (00-23), mm is minutes (00-59), and ss is
seconds (00-59). A 24-hour clock is used; therefore, 8:00 PM is shown as
20:00:00.
TIMER
The TIMER function can be used with the RANDOMIZE statement to generate a
random number. It can also be used to time programs or parts of programs.
■ Example
TYPE usertype elementname AS typename elementname AS typename .
The TYPE statement takes the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
UBOUND(array«,dimension»)
The argument dimension is an integer from 1 to the number of dimensions in
array. For an array dimensioned as follows, UBOUND returns the values
listed below:
UCASE$ (stringexpression)
The stringexpression argument can be any string expression. The UCASE$
function works with both variable- and fixed-length strings. The UCASE$
and LCASE$ statements are helpful in making string comparisons case
insensitive.
VAL(stringexpression)
The stringexpression is a sequence of characters that can be interpreted
as a numeric value. The VAL function stops reading the string at the first
character that it cannot recognize as part of a number. The VAL function
also strips leading blanks, tabs, and line feeds from the argument string.
WHILE condition . . .
If the condition is true (that is, if it does not equal zero), then any
intervening statements are executed until the WEND statement is
encountered. BASIC then returns to the WHILE statement and checks
condition. If it is still true, the process is repeated. If it is not true
Only supports COLOR FG, BG
COLOR «foreground»«,«background»«,border»» Screen mode 0 COLOR «background»«,palette» Screen mode 1 COLOR «foreground»«,background» Screen modes 7-10 COLOR «foreground» Screen modes 12-13
With the COLOR statement, you can set the foreground and background colors
for the display. In screen mode 0 a border color can also be selected. In
screen mode 1 no foreground color can be selected, but one of two
four-color palettes can be selected for use with graphics statements. In
Only single line syntax supported
DEF FNname«(parameterlist)» = expression DEF FNname«(parameterlist)» . .
The DEF FN statement takes the following arguments:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Argument Description
Partial support for keycodes
INKEY$
The INKEY$ function returns a one- or two-byte string containing a
character read from the standard input device. A null string is returned
if no character is waiting there. A one-character string contains the
actual character read from the keyboard, while a two-character string
Semicolon before prompt string not supported
INPUT«;»«"promptstring"{; | ,}» variablelist The following list describes the parts of the INPUT statement:
Part Description
──────────────────────────────────────────────────────────────────────────
Files not supported
INPUT$(n«,«#»filenumber»)
The n is the number of characters (bytes) to read from the file. The
filenumber is the number that was used in opening the file.
If the file is opened for random access, the argument n must be less than
Only supports strings and arrays
LEN(stringexpression) LEN(variable)
In the first form, LEN returns the number of characters in the argument
stringexpression. The second syntax returns the number of bytes required
by a BASIC variable. This syntax is particularly useful for determining
the correct record size of a random-access file.
Semicolon before prompt string not supported
LINE INPUT«;» «"promptstring";» stringvariable
The promptstring is a string constant displayed on the screen before input
is accepted. A question mark is not printed unless it is part of the
promptstring. All input from the end of promptstring to the carriage
return is assigned to stringvariable.
"start" and "stop" not supported
LOCATE«row»«,«column»«,«cursor»«,«start»«,stop»»»»
The following list describes the LOCATE statement's arguments:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Argument Description
Only # and & formatting supported
PRINT USING formatstring; expressionlist «{, | ;}» The formatstring is a string literal (or variable) containing literal
characters to print (such as labels) and special formatting characters.
These formatting characters determine the field and the format of the
printed strings or numbers. Spaces, commas, and semicolons in the
Ignored - RND always returns randomly seeded number
RANDOMIZE«expression»
If you omit expression, BASIC pauses and asks for a value by printing
Random Number Seed (-32768 to 32767)?
Always returns randomly seeded number
RND«(n)»
The value of n determines how RND generates the next random number:
Argument Number Returned
──────────────────────────────────────────────────────────────────────────
Only screen mode 0 supported
SCREEN «mode» «,«colorswitch» »«,«apage» »«,«vpage»»
The SCREEN statement selects a screen mode appropriate for a particular
combination of display and adapter. Later sections describe the available
modes for specific adapters. The following list describes the arguments of
the SCREEN statement:
BLOAD filespec «,offset»
The BLOAD statement takes the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
BSAVE filespec,offset,length
The BSAVE statement has the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
CALL name «(call-argumentlist)» name «call-argumentlist» CALLS name «(calls-argumentlist)»
The following list describes the parts of the CALL statement:
Argument Description
──────────────────────────────────────────────────────────────────────────
CHAIN filespec
The filespec is a string expression that identifies the program to which
control is passed. The filespec may include a path specification. Programs
running within the QuickBASIC environment assume a .BAS extension (if no
extension is given) and cannot chain to executable files (files with a
CHDIR pathspec
The pathspec is a string expression identifying the directory that is to
become the default directory. The pathspec must have fewer than 64
characters. It has the following syntax:
CIRCLE «STEP» (x,y),radius«,«color»«,«start»«,«end»«,aspect»»»»
The following list describes the parts of the CIRCLE statement:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Part Description
CLEAR «,,stack»
The CLEAR statement performs the following actions:
■ Closes all files and releases the file buffers
CLOSE ««#» filenumber «,«#» filenumber»...»
The CLOSE statement complements the OPEN statement.
The filenumber is the number under which the file was opened. A CLOSE
statement with no arguments closes all open files and devices.
COMMAND$
The COMMAND$ function returns the complete command line entered after your
BASIC program name, including optional parameters. COMMAND$ removes all
leading blanks from the command line and converts all letters to uppercase
(capital letters). The COMMAND$ function can be used in stand-alone
CVI(2-byte-string) CVS(4-byte-string) CVL(4-byte-string) CVD(8-byte-string)
CVI, CVS, CVL, and CVD are used with a FIELD statement to read real
numbers from a random-access file. The functions take strings defined in
the FIELD statement and convert them to a value of the corresponding
numeric type. The functions are the inverse of MKI$, MKS$, MKL$, and MKD$:
DECLARE FUNCTION name «CDECL» «ALIAS "aliasname"»«(«parameterlist»)» DECLARE SUB name «CDECL» «ALIAS "aliasname"»«(«parameterlist»)»
The following list describes the parts of the DECLARE statement:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Part Description
DEF SEG «=address»
For BLOAD, BSAVE, CALL ABSOLUTE, PEEK, and POKE, address is used as the
segment. The address is a numeric expression returning an unsigned integer
in the range 0-65,535. A value outside this range produces the error
message Illegal function call. The previous segment is retained if an
DRAW stringexpression
The DRAW statement combines many of the capabilities of the other graphics
statements into a graphics macro language, as described below under
"Cursor-Movement Commands" and "Angle, Color, and Scale-Factor Commands."
This macro language defines a set of characteristics that can be used to
ENVIRON$ (environmentstring) ENVIRON$ (n)
The environmentstring is a string constant or variable containing the name
of an environment variable. The argument n is a numeric expression.
If you specify an environmentstring name, but it cannot be found in the
ENVIRON stringexpression
The stringexpression must be of the form parameterid=text, or the form
parameterid text. Everything to the left of the equal sign or space is
assumed to be a parameter, and everything to the right, text.
EOF(filenumber)
The EOF function returns -1 (true) if the end of a sequential file has
been reached. Use the EOF function to test for end-of-file while inputting
data. In this way you may avoid the Input past end error message.
ERASE arrayname «,arrayname...»
The arrayname arguments are the names of arrays to erase. ERASE has
different effects on static and dynamic arrays.
The ERASE statement sets the elements of a static array to zeros in the
ERDEV ERDEV$
ERDEV is an integer function that returns an error code from the last
device to declare an error. ERDEV$ is a string function that returns the
name of the device generating the error. Because ERDEV and ERDEV$ return
meaningful information only after an error, they are usually used in error
ERR ERL
After an error, the function ERR returns the code for the error, and the
ERL function returns the line number where the error occurred. Because ERR
and ERL return meaningful values only after an error, they are usually
used in error-handling routines to determine the error and the corrective
ERROR integerexpression
The integerexpression represents the error code. It must be greater than 0
and less than or equal to 255. If the integerexpression is an error code
already used by BASIC, then the ERROR statement simulates the occurrence
of that error and prints the corresponding error message.
FIELD «#»filenumber, fieldwidth AS stringvariable...
The following list describes the FIELD statement's arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
FILEATTR(filenumber,attribute)
The FILEATTR function takes the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
FILES «filespec»
The filespec is a string variable or constant that includes either a file
name or a path name, and an optional device designation.
If you omit filespec, the FILES statement lists all the files in the
FRE(numeric-expression) FRE(stringexpression)
The FRE function returns the following values when it has a numeric
argument (numeric-expression):
Argument Value Returned
FREEFILE
The FREEFILE function returns the next valid unused file number.
You can use this function to avoid having SUB or FUNCTION procedures use
file numbers that are already in use.
GET «STEP»(x1,y1) - «STEP»(x2,y2),arrayname«(indices)»
The list below describes the parts of the GET statement:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Part Description
GET «#»filenumber«,«recordnumber»«,variable»»
The following list describes the GET statement's arguments:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Argument Description
INPUT #filenumber, variablelist
The filenumber is the number used when the file was opened for input. The
variablelist contains the names of the variables that are assigned values
read from the file. (The variable type must match the type specified by
the variable name.)
KEY n, stringexpression KEY LIST KEY ON KEY OFF
The placeholder n is a number representing the FUNCTION key. The values
for n are 1 to 10 for the FUNCTION keys, and 30 and 31 for FUNCTION keys
F11 and F12 on 101-key keyboards. The stringexpression is a string of up
to 15 characters that is returned when the FUNCTION key is pressed. If the
KEY(n) ON KEY(n) OFF KEY(n) STOP
The argument n is the number of a FUNCTION key, a cursor-direction key, or
a user-defined key. (See the KEY statement for information on assigning
soft-key values to FUNCTION keys.) The values of n are as follows:
KILL filespec
The KILL statement is similar to the DOS ERASE or DEL commands.
KILL is used for all types of disk files: program files, random data
files, and sequential data files. The filespec may contain question marks
LINE ««STEP» (x1,y1)»-«STEP» (x2,y2) «,«color»«,«B«F»»«,style»»»
The coordinates (x1,y1) and (x2,y2) specify the endpoints of the line;
note that the order in which these endpoints appear is unimportant, since
a line from (10,20) to (120,130) is the same as a line from (120,130) to
(10,20).
LINE INPUT #filenumber,stringvariable
The filenumber is the number used to open the file. The stringvariable is
the variable the line is assigned to.
The LINE INPUT # statement reads all characters in the sequential file up
LOC(filenumber)
The filenumber is the number used in the OPEN statement to open the file.
With random-access files, the LOC function returns the number of the last
record read from or written to the file. With sequential files, LOC
returns the current byte position in the file, divided by 128. With binary
LOCK «#» filenumber «,{record | «start» TO end}»
.
.
.
These statements are used in networked environments where several
processes might need access to the same file. The LOCK and UNLOCK
statements take the following arguments:
LOF(filenumber)
The argument filenumber is the number used in the OPEN statement. When a
file is opened in any mode, the LOF function returns the size of the file
in bytes.
LSET {stringvariable=stringexpression | stringexpression1=
stringexpression2} The stringvariable is usually a random-access file field defined in a
FIELD statement, although it can be any string variable. The
stringexpression is the value assigned to the variable.
MID$(stringvariable,start«,length»)=stringexpression
The MID$ statement has the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
MKDIR pathname
The pathname is a string expression specifying the name of the directory
to be created. The pathname must be a string of less than 128 characters.
The MKDIR statement works like the DOS command MKDIR; the syntax in BASIC
MKSMBF$(single-precision-expression) MKDMBF$(double-precision-expression)
These functions are used to write real numbers to random-access files
using Microsoft Binary format. They are particularly useful for
maintaining data files created with older versions of BASIC.
MKI$(integerexpression) MKS$(single-precision-expression) MKL$(long-integer-expression) MKD$(double-precision-expression)
The MKI$, MKS$, MKL$, and MKD$ functions are used with FIELD and PUT
statements to write real numbers to a random-access file. The functions
take numeric expressions and convert them to strings that can be stored in
the strings defined in the FIELD statement. The functions are the inverse
NAME oldfilename AS newfilename
The NAME statement is similar to the DOS RENAME command. NAME can move a
file from one directory to another but cannot move a directory.
The arguments oldfilename and newfilename are string expressions each of
ON event GOSUB {linenumber | linelabel } The ON event statement lets you specify a subroutine that is executed
whenever an event occurs on a specified device. The following list
describes the parts of the statement:
ON ERROR GOTO line
The line argument is the line number or line label of the first line in
the error-handling routine. This line must appear in module-level code.
If line cannot be found in the module where the error occurred, or if
ON expression GOSUB {line-number-list | line-label-list }
ON expression GOTO {line-number-list | line-label-list } The expression argument can be any numeric expression (expression is
rounded to an integer before the ON...GOSUB or ON...GOTO is evaluated).
The line-number-list or line-label-list consists of a list of line numbers
or line labels, separated by commas. The value of expression determines
ON UEVENT GOSUB { linenumber | linelabel } The linenumber or linelabel argument is the number or label of the first
line in the event-handling routine. ON UEVENT GOSUB lets your program
branch to an event-handling routine when a user-defined event occurs. The
event is usually a hardware interrupt.
OPEN file «FOR mode1» «ACCESS access» «lock» AS «#» filenum «LEN=reclen» OPEN mode2,«#»filenum, file «,reclen»
The file is a string expression that specifies an optional device,
followed by a file name or path name conforming to the DOS file-naming
conventions.
OPTION BASE n
The OPTION BASE statement is never required. It is used to change the
default lower bound for array subscripts.
The value of n must be either 0 or 1. The default base is 0. If the
PAINT «STEP» (x,y)«,«paint» «,«bordercolor» «,background»»»
The following list describes the parts of the PAINT statement:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Part Description
PALETTE «attribute,color» PALETTE USING array-name «(array-index)»
The PALETTE statement takes the following arguments:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Argument Description
PCOPY sourcepage, destinationpage
The sourcepage is an integer expression in the range 0 to n, where n is
the maximum number of pages determined by the current video-memory size
and the size per page for the current screen mode.
PEEK(address)
The returned value is an integer in the range 0-255. The argument address
is a value in the range 0-65,535. The argument address is treated as the
offset from the current default segment (as set by the DEF SEG statement).
PLAY commandstring
The commandstring is a string expression containing one or more of the
commands listed below.
The PLAY statement uses a concept similar to DRAW in that it embeds a
PLAY (n)
The argument n is a dummy argument and may be any numeric value.
PLAY(n) will return 0 when the user is in music-foreground mode.
PLAY ON PLAY OFF PLAY STOP
These statements are used with the ON PLAY statement to trap play events.
When a PLAY OFF statement is executed, the event-trapping subroutine is
not performed and the event is not remembered.
PMAP (expression, function)
The argument expression indicates the coordinate of the point to be
mapped. The argument function can have one of the four following values:
Value Description
POINT (x,y) POINT (number)
The coordinates x and y refer to the pixel being evaluated by the POINT
function. When called with two coordinates, POINT returns the color number
of the indicated pixel. If the specified pixel is out of range, POINT
returns the value -1.
POKE address,byte
The expression address is a value that represents the address of the
memory location; address must be in the range 0-65,535. The expression
byte is the data byte to be written; it is an integer value in the range
0-255.
PRESET «STEP»(xcoordinate,ycoordinate) «,color»
PRESET works exactly like PSET, except that if the color is not specified,
the background color is selected. The following list describes the parts
of the PRESET statement:
PRINT #filenumber,«USING stringexpression;» expressionlist «{, | ;}» The filenumber is the number specified when the file was opened for
output. The stringexpression consists of formatting characters as
described under PRINT USING. The expressions in expressionlist are the
numeric or string expressions to be written to the file. Spaces, commas,
PSET «STEP»(xcoordinate,ycoordinate) «,color»
The following list describes the parts of the PSET statement:
Part Description
──────────────────────────────────────────────────────────────────────────
PUT «STEP» (x, y), arrayname«(indices)» «,actionverb»
The parts of the PUT statement are described as follows:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Part Description
PUT «#»filenumber«,«recordnumber»«,variable»»
PUT «#»filenumber«,{recordnumber|recordnumber, variable|,variable}» The following list describes the parts of the PUT statement:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Argument Description
REDIM «SHARED» variable(subscripts)«AS type» «,variable(subscripts)«AS typ e»»...
The REDIM statement has the following arguments:
Arguments Description
──────────────────────────────────────────────────────────────────────────
RESET
The RESET statement closes all open disk files and writes data still in
the file buffers to disk. All files must be closed before a disk is
removed from its drive.
RESUME «0»
RESUME NEXT
RESUME { linenumber | linelabel } The different forms of the RESUME statement redirect program flow as
described in the following list:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
RMDIR pathname
The pathname is the name of the directory that is to be deleted. The
pathname must be a string of less than 128 characters. The directory to be
removed must be empty except for the working directory ('.') and the
parent directory ('..'); otherwise, one of two error messages is printed,
RSET stringvariable=stringexpression
The stringvariable is usually a random-access file field defined in a
FIELD statement, although it can be any string variable. The
stringexpression is the value assigned to the variable.
RUN «{ linenumber | filespec }» The RUN statement accepts the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
SADD(stringvariable)
The SADD function returns the address of a string as an offset (near
pointer) from the current data segment. The offset is a two-byte integer.
SADD is most often used in mixed-language programming.
SCREEN(row,column«,colorflag»)
The following list describes the SCREEN function's arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
SEEK(filenumber)
The filenumber is the number used in the OPEN statement to open the file.
SEEK returns a value in the range 1 to 2,147,483,647 (equivalent to
2^31-1).
SEEK «#»filenumber,position
The filenumber is an integer number used in the OPEN statement to open the
file.
The position is a numeric expression indicating where the next read or
SETMEM(numeric-expression)
The SETMEM function increases or decreases the far heap by the number of
bytes indicated by numeric-expression. If the numeric-expression is
negative, SETMEM decreases the far heap by the indicated number of bytes.
When the numeric-expression is positive, SETMEM attempts to increase the
SHELL «commandstring»
The commandstring must be a valid string expression containing the name of
a program to run and any program options.
Any .COM file, .EXE file, .BAT program, or DOS function that runs under
SOUND frequency,duration
The frequency is the desired frequency in hertz (cycles/second). It must
be a numeric expression returning an integer in the range 37-32,767.
The duration is the duration in clock ticks. (There are 18.2 clock ticks
TIMER ON TIMER OFF TIMER STOP
TIMER ON enables timer event trapping by an ON TIMER statement (see the
statement ON event). While trapping is enabled, a check is made after
every statement to see if the specified time has elapsed. If it has, the
ON TIMER event-handling routine is executed.
TRON TROFF
In the QuickBASIC environment, executing a TRON statement has the same
effect as selecting Trace On from the Debug menu──each statement is
highlighted on the screen as it executes.
UEVENT ON UEVENT OFF UEVENT STOP
The effects of the UEVENT statements are like that of other event-trapping
statements. When UEVENT ON is executed, the event-trapping routine is
enabled. Occurrences of the event trigger execution of the event-handling
routine.
UNLOCK «#» filenumber «,{record | «start» TO end}» The UNLOCK statement is used only after a LOCK statement. See the LOCK
statement for a complete discussion.
For binary-mode files, the arguments record, start, and end represent the
In previous versions of QuickBASIC, the only events that could be trapped
were those already defined in the language: COM, KEY, PEN, PLAY, STRIG and
TIMER. There was no way to define your own event.
VARPTR(variablename) VARSEG(variablename)
The variablename may be any BASIC variable, including a record variable or
record element. The VARPTR function returns an unsigned integer that is
the offset of the variable within its segment. The VARSEG function returns
an unsigned integer that is the segment part of the variable's address. If
VARPTR$(variablename)
The variablename is the name of a variable in the program. If variablename
is an array element, then the array must be dimensioned before the VARPTR$
function is used. The array must be an array of variable-length strings.VIEW ««SCREEN» (x1,y1)-(x2,y2) «,«color» «,border»»»
The list below describes the parts of the VIEW statement:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Part Description
VIEW PRINT «topline TO bottomline»
The topline argument is the number of the upper line in the viewport; the
bottomline is the number of the lower line.
Without topline and bottomline parameters, the VIEW PRINT statement
WIDTH «columns»«,lines»
WIDTH {#filenumber | device},width
WIDTH LPRINT width Both files and devices can be assigned an output-line width. The different
forms of the WIDTH statement are explained in the following list:
╓┌─┌────────────────────────────────────┌────────────────────────────────────╖
WINDOW ««SCREEN» (x1,y1)-(x2,y2)»
The WINDOW statement allows the user to create a customized coordinate
system to draw lines, graphs, or objects without being constrained by the
screen's physical coordinates (the dimensions of the screen). This is done
by redefining the screen-border coordinates with the "view coordinates"
WRITE «expressionlist»
If expressionlist is omitted, a blank line is written. If expressionlist
is included, the values of the expressions are written to the screen. The
expressions in the list may be numeric and/or string expressions. They
must be separated by commas.
WRITE #filenumber,expressionlist
The filenumber is the number used in the OPEN statement. The file must be
opened in OUTPUT or APPEND mode. The expressions in the argument
expressionlist are string and/or numeric expressions, separated by commas.
If you omit the expressionlist, the WRITE # statement writes a blank line
CALL ABSOLUTE («argumentlist,»integervariable)
The CALL ABSOLUTE statement takes the following arguments:
Argument Description
──────────────────────────────────────────────────────────────────────────
CALL INT86OLD (int_no,in_array(),out_array()) CALL INT86XOLD (int_no,in_array(),out_array())
The CALL INTERRUPT statement provides an easier way to make DOS system
calls. See the entry for CALL INTERRUPT for more information. The
following list describes the arguments to INT86OLD and INT86XOLD:
CALL INTERRUPT (interruptnum,inregs,outregs) CALL INTERRUPTX (interruptnum,inregs,outregs)
The following list describes the arguments for the CALL INTERRUPT and CALL
INTERRUPTX statements:
Argument Description
COM(n) ON COM(n) OFF COM(n) STOP
The parameter n is the number of the communications port; n can be either
1 or 2.
The COM ON statement enables communications event trapping. If a character
COMMON «SHARED» «/blockname/» variablelist
The following list describes the parts of the COMMON statement:
╓┌─┌────────────────────────┌────────────────────────────────────────────────╖
Part Description
CVSMBF (4-byte-string) CVDMBF (8-byte-string)
The CVSMBF and CVDMBF functions allow you to read old random-access files
containing real numbers stored as strings in Microsoft Binary format.
These functions convert the string read from the old file to an
IEEE-format number:
DATE$ = stringexpression
The DATE$ statement is the complement of the DATE$ function.
The stringexpression must have one of the following forms, where mm
(01-12) and dd (01-31) are the month and day, and yy and yyyy (1980-2099)
INP(port)
The port must be an integer in the range 0-65,535. The INP function
complements the OUT statement.
The INP and OUT statements give a BASIC program direct control over the
IOCTL$ («#» filenumber)
The filenumber is the BASIC file number used to open the device. The
IOCTL$ function is most frequently used to test whether an IOCTL statement
succeeded or failed or to obtain current status information.
IOCTL «#»filenumber, string
The filenumber is the BASIC file number used to open the device. The
string is the command sent to the device. Commands are specific to the
device driver. See the documentation for the device driver to find out
what the valid IOCTL commands are. An IOCTL control data string can be up
LPOS(n)
The argument n is the index of the printer being tested. For example,
LPT1: would be tested with LPOS(1), while LPT2: would be tested with
LPOS(2), and so on.
LPRINT «expressionlist» «{;|,}»
LPRINT USING formatstring; expressionlist «{;|,}» These statements function in the same way as the PRINT and PRINT USING
statements except that output goes to the line printer and the filenumber
option is not permitted.
OPEN "COMn: optlist1 optlist2" «FOR mode» AS «#»filenum «LEN=reclen»
COMn: is the name of the device to be opened. The n argument is the number
of a legal communications device, such as COM1: or COM2:. The first list
of options, optlist1, has the following form:
OUT port, data
The following list describes the arguments of the OUT statement:
Argument Description
──────────────────────────────────────────────────────────────────────────
PEN(n)
The argument n indicates what value is to be returned. It is a numeric
expression in the range 0-9.PEN ON PEN OFF PEN STOP
The PEN ON statement enables lightpen-event trapping by using an ON PEN
statement. The pen is initially off. A lightpen event occurs whenever the
lightpen is activated by pressing the tip to the screen or pressing the
touch ring. A PEN ON statement must be executed before any read-pen
STICK(n)
The argument n is a numeric expression whose value is an unsigned integer
in the range 0 to 3:
Argument Value Returned
STRIG(n)
STRIG {ON | OFF} The STRIG function is used to test the joystick trigger status. In
previous versions of BASIC, the statement STRIG ON enables testing of the
joystick triggers; STRIG OFF disables joystick trigger testing. QuickBASIC
ignores STRIG ON and STRIG OFF statements──the statements are provided for
STRIG(n) ON STRIG(n) OFF STRIG(n) STOP
The argument, n, is a numeric expression indicating the joystick button to
trap:
Value Button
TIME$=stringexpression
The stringexpression must be in one of the following forms:
Form Description
──────────────────────────────────────────────────────────────────────────
WAIT portnumber,and-expression«,xor-expression»
The following list describes the arguments of the WAIT statement:
Argument Description
──────────────────────────────────────────────────────────────────────────