BINARY

From QB64.org wiki
Redirect page
Jump to: navigation, search

BINARY is used in an OPEN statement to work with the file or port device manipulating its bytes directly.


Syntax

OPEN fileName$ FOR BINARY AS #fileNumber%


Description

  • OPEN FOR BINARY creates the file if the fileName$ does not exist.
  • fileName$ is the name of the file to open, but could also configure a port.
  • #fileNumber% is the number that will represent the file when performing file operations.
  • BINARY files use GET # and PUT # to read or write the file at any byte position.
  • In version 1.000 and up you can use LINE INPUT in BINARY mode for faster access to text file data.
  • QBasic's BSAVE or BINARY save files can be read using BINARY mode.
  • BINARY mode ignores any LEN = recordlength statement in the OPEN statement.
  • Ports can also be opened in BINARY mode. See: OPEN COM


Examples

Example 1: Shows how a PUT variable value is converted to an ASCII string _MK$ format in a BINARY file.

DIM int64 AS _INTEGER64 DIM byte8 AS STRING * 8 int64 = 12345678 PRINT int64 OPEN "temp64.tmp" FOR BINARY AS #1 PUT #1, , int64 'the file size will be 8 bytes CLOSE PRINT "Press a key to read the file!" K$ = INPUT$(1) OPEN "temp64.tmp" FOR BINARY AS #1 GET #1, , byte8 'GET the value as a string PRINT "text string: "; byte8 'show that string is in _MK$ format PRINT _CV(_INTEGER64, byte8) 'convert to numerical value CLOSE

Note: The numerical value does not need to be converted if the file is read using the same numerical variable type as written.


Example 2: A binary file viewer that can view integer values. The type of value can be changed at DIM.

SCREEN _NEWIMAGE(1000, 600, 256) _SCREENMOVE _MIDDLE DIM value AS INTEGER 'value type can be changed LINE INPUT ; "Enter a BINARY filename to open: ", file$ PRINT " Press S to restart!" IF LEN(file$) THEN OPEN file$ FOR BINARY AS #1 ELSE END IF LOF(1) = 0 THEN PRINT "Empty file!": END DO FOR i = 1 TO 16 x = x + 1 GET #1, , value IF EOF(1) THEN EXIT DO PRINT value; NEXT PRINT CHR$(27); x; "@"; row K$ = INPUT$(1) IF UCASE$(K$) = "S" THEN CLS: x = 0: row = 0: PRINT "Restarted!": SEEK 1, 1 IF x = 256 THEN x = 0: row = row + 1: PRINT LOOP UNTIL K$ = CHR$(27) CLOSE #1 PRINT "Press Escape to exit!" DO: _LIMIT 100 LOOP UNTIL INKEY$ = CHR$(27) SYSTEM


See also



Navigation:
Go to Keyword Reference - Alphabetical
Go to Keyword Reference - By usage
Go to Main WIKI Page