PRINT (file statement): Difference between revisions

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{{PageParameters}}
{{PageParameters}}
* {{Parameter|fileNumber&}} is the file number of a file or device opened for writing. See {{KW|OPEN}}.
* {{Parameter|fileNumber&}} is the file number of a file or device opened for writing. See [[OPEN]].
* {{Parameter|expression}} is a numeric or string expression to be written to the file. Quotes will be removed from strings.
* {{Parameter|expression}} is a numeric or string expression to be written to the file. Quotes will be removed from strings.
* The print statement can be followed by a [[semicolon]] to stop the print cursor or a [[comma]] to tab the next print.
* The print statement can be followed by a [[semicolon]] to stop the print cursor or a [[comma]] to tab the next print.
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** If a numeric literal is in scientific notation, the number is also written in scientific notation. [[PRINT USING (file statement)|PRINT #, USING]] can return actual rounded numerical values in string form.
** If a numeric literal is in scientific notation, the number is also written in scientific notation. [[PRINT USING (file statement)|PRINT #, USING]] can return actual rounded numerical values in string form.
** The numerical value is always followed by a space character unless [[STR$]] is used to convert it to a string value.
** The numerical value is always followed by a space character unless [[STR$]] is used to convert it to a string value.
* Whenever [[PRINT (file statement)|PRINT #]] moves the file cursor to a new file row, a carriage return character ({{KW|CHR$|CHR$(13)}}) followed by a line feed character ({{KW|CHR$|CHR$(10)}}) is written. The combination are referred to as the "CRLF" character.
* Whenever [[PRINT (file statement)|PRINT #]] moves the file cursor to a new file row, a carriage return character ([[CHR$|CHR$(13)]]) followed by a line feed character ([[CHR$|CHR$(10)]]) is written. The combination are referred to as the "CRLF" character.
* '''Note: [[RANDOM]] and [[BINARY]] files are not affected by PRINT # statements to them and will create a syntax error in QB64!'''
* '''Note: [[RANDOM]] and [[BINARY]] files are not affected by PRINT # statements to them and will create a syntax error in QB64!'''



Latest revision as of 00:52, 25 January 2023

The PRINT # statement prints numeric or string expressions to a sequential file, IO port or device.


Syntax

PRINT #fileNumber&, [ [expression] [{;|,] ... ]


Parameters

  • fileNumber& is the file number of a file or device opened for writing. See OPEN.
  • expression is a numeric or string expression to be written to the file. Quotes will be removed from strings.
  • The print statement can be followed by a semicolon to stop the print cursor or a comma to tab the next print.


Usage:

  • STRING values will be stripped of leading and trailing quotation marks when printed to the file. Use CHR$(34) to add quotes to a file.
  • separator is used to separate multiple expressions and specifies how the file cursor is to be moved before writing the next expression. It can be one of the following:
    • semi-colon (;) - specifies that the print cursor stop immediately after the print. A subsequent print will start there.
    • comma (,) - specifies that the file cursor is to move to the next 14-column tab-stop. If the file cursor is at column 56 or greater, it is moved to the next file row at column 1.
  • If separator is not used at the end of the expression list, the file cursor moves to the next file row at column 1.
  • PRINT # can use the + concatenation operator or semicolons to combine strings.
  • SPC(n%) - specifies that n% space characters will be written in a print.
  • TAB(column%) - specifies that the file cursor is to move to a column number column%. If the file cursor is beyond that column, it is moved to that column on the next file row.
  • When printing literal or variable numerical values the following rules apply:
    • If the value is positive, the number is prefixed with a space character, otherwise, the number is prefixed with a negative sign (-).
    • If the value is an INTEGER (whole number), no decimal point or fractional part will be written.
    • If the value is not an integer (whole number) and has zero for a coefficient, no leading zero is written. For example, -0.123 is written as "-.123 "
    • If a numeric literal is in scientific notation, the number is also written in scientific notation. PRINT #, USING can return actual rounded numerical values in string form.
    • The numerical value is always followed by a space character unless STR$ is used to convert it to a string value.
  • Whenever PRINT # moves the file cursor to a new file row, a carriage return character (CHR$(13)) followed by a line feed character (CHR$(10)) is written. The combination are referred to as the "CRLF" character.
  • Note: RANDOM and BINARY files are not affected by PRINT # statements to them and will create a syntax error in QB64!


Example: Prints data to a text file sequentially and reads it back to the program screen as one line of text.

filename$ = "testfile.dat"
x = 1: y = 2: z$ = "Three"

OPEN filename$ FOR OUTPUT AS #1 'opens and clears an existing file or creates new empty file

PRINT #1, x, y, z$

CLOSE #1

PRINT "File created with data. Press a key!"

K$ = INPUT$(1) 'press a key

OPEN filename$ FOR INPUT AS #2 'opens a file to read it

LINE INPUT #2, text$

CLOSE #2

PRINT text$
WRITE text$

END
File content: PRINT string file values will not include the enclosing quotation marks but can be read by LINE INPUT as text.
 1             2            Three 
Screen output: PRINT string values will not display enclosing quotation marks. WRITE screen displays will.
 1             2            Three
" 1             2            Three"


See also



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