File name verfication

[RhoSigma]

This is my verification function, feel free to use it and/or adapt to your needs:

Code: (Select All)

LINE INPUT "Filename: "; f$

IF ValidFilename%(f$) THEN
    PRINT "Filename is ok."
ELSE
    PRINT "Filename contains invalid chars."
END IF
END

FUNCTION ValidFilename% (file$)
'--- so far, assume invalid ---
ValidFilename% = 0
'--- now check all chars ---
FOR i% = 1 TO LEN(file$)
    SELECT CASE ASC(file$, i%)
        CASE 34, 42, 47, 60, 62, 63, 124
            'invalid chars, list above is for Windows,
            'may need adjustment for other OS
            EXIT FUNCTION
    END SELECT
NEXT i%
'--- check succesfully passed ---
ValidFilename% = -1
END FUNCTION