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Samuel Gomes edited this page Nov 8, 2022 · 1 revision

The FILES statement is used to print a list of files in the current directory using a file specification.

Syntax

FILES [fileSpec$]

Description

  • fileSpec$ is a string expression or variable containing a path when required.
  • fileSpec$ can use the * and ? wildcard specifications:
    • * denotes one or more wildcard characters in a filename or path specification as any legal file name character(s).
    • ? denotes one wildcard letter in a filename or path specification as any legal filename character.
  • If fileSpec$ is omitted, it is assumed to be "." (all files and folders in the current directory).
  • Illegal filename characters in QB64 include * > < : " | \ / with any amount of dot extensions being allowed in Windows.
  • FILES lists can make the screen roll up. Try using SHELL "DIR" with the /P option. DIR command.

QBasic

  • Illegal filename characters in QBasic included *** ? , > < ; : " | \ / + [ ]** and more than one dot extension in DOS.

Example(s)

Finding a list of all BAS files in the current folder.

FILES "*.BAS"

Alternative file list solutions

Alternative 1: The DIR$ function adapted from PDS (7.1) returns a filename or a list when more than one exist. The file spec can use a path and/or wildcards.

FOR i = 1 TO 2
  PRINT
  LINE INPUT "Enter a file spec: ", spec$
  file$ = DIR$(spec$) 'use a file spec ONCE to find the last file name listed
  PRINT DIRCount%, file$, 'function can return the file count using SHARED variable
  IF DIRCount% > 1 THEN
    DO
      K$ = INPUT$(1)
      file$ = DIR$("") 'use an empty string parameter to return a list of files!
      PRINT file$,
    LOOP UNTIL LEN(file$) = 0 'file list ends with an empty string
  END IF
NEXT

END

FUNCTION DIR$ (spec$)
CONST TmpFile$ = "DIR$INF0.INF", ListMAX% = 500 'change maximum to suit your needs
SHARED DIRCount% 'returns file count if desired
STATIC Ready%, Index%, DirList$()
IF NOT Ready% THEN REDIM DirList$(ListMAX%): Ready% = -1 'DIM array first use
IF spec$ > "" THEN 'get file names when a spec is given
  SHELL _HIDE "DIR " + spec$ + " /b > " + TmpFile$
  Index% = 0: DirList$(Index%) = "": ff% = FREEFILE
  OPEN TmpFile$ FOR APPEND AS #ff%
  size& = LOF(ff%)
  CLOSE #ff%
  IF size& = 0 THEN KILL TmpFile$: EXIT FUNCTION
  OPEN TmpFile$ FOR INPUT AS #ff%
  DO WHILE NOT EOF(ff%) AND Index% < ListMAX%
    Index% = Index% + 1
    LINE INPUT #ff%, DirList$(Index%)
  LOOP
  DIRCount% = Index% 'SHARED variable can return the file count
  CLOSE #ff%
  KILL TmpFile$
ELSE IF Index% > 0 THEN Index% = Index% - 1 'no spec sends next file name
END IF
DIR$ = DirList$(Index%)
END FUNCTION

Explanation: The function will verify that a file exists (even if it is empty) by returning its name, or it returns an empty string if no file exists. It can return a list of file names by using an empty string parameter("") after sending a wildcard spec to get the first file name. The number of file names found is returned by using the SHARED variable, DIRCount%. Unlike the PDS DIR$ function, it must use an empty string parameter as QB64 doesn't support optional parameters. The function does not delete empty files.

Alternative 2:

  • The member-contributed FILELIST$ function uses the mouse and does not affect your program screens. It can verify that a file name exists or display a list of long and short file names to choose from. It also avoids program errors when a file name does not exist.

See Also

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