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+--- Thread: Making text unreadable, 1 sample code works, 2 do not work (/showthread.php?tid=112)
Making text unreadable, 1 sample code works, 2 do not work - Robert Alvarez - 22.01.2026
Found three code samples in the internet to make text unreadable.
First one can read text and encrypt it and decrypt .
The second and third seems to encrypt it but decrypt does not work.
First sample code:
Code:
#COMPILE EXE
#INCLUDE "WIN32API.INC"
GLOBAL hDlg AS LONG
CALLBACK FUNCTION ENDPROG()
DIALOG END CBHNDL, 1
END FUNCTION
FUNCTION PBMAIN () AS LONG
$REGISTER NONE
LOCAL result, i AS LONG
'1. Basic Character Shift (Caesar Cipher Style)
OPEN "secret 1a.dat" FOR OUTPUT AS #1
text$ = "This is my secret message."
FOR i = 1 TO LEN(text$)
PRINT #1, CHR$(ASC(MID$(text$, i, 1)) + 5);
NEXT
CLOSE #1
OPEN "secret 1a.dat" FOR INPUT AS #1: LINE INPUT #1, text$
? text$ 'encryt
FOR i = 1 TO LEN(text$)
text1$=text1$+CHR$(ASC(MID$(text$, i, 1)) - 5)
NEXT
? text1$ 'decreypt
DIALOG NEW 0, "TEST 1", ,, 200, 150, %WS_MINIMIZEBOX+%WS_SYSMENU, 0 TO hDlg
CONTROL ADD LABEL, hDlg, 100, "LABEL 1",80, 40, 60, 14,
CONTROL ADD BUTTON,hDlg, 202, "&Exit Program",100, 100,55, 14, CALL ENDPROG
CONTROL SET FOCUS hDlg, 202
DIALOG SHOW MODAL hDlg TO result
END FUNCTIONSecond sample code:
Code:
#COMPILE EXE
#INCLUDE "WIN32API.INC"
GLOBAL hDlg AS LONG
CALLBACK FUNCTION ENDPROG()
DIALOG END CBHNDL, 1
END FUNCTION
FUNCTION PBMAIN () AS LONG
$REGISTER NONE
LOCAL result, i, key AS LONG
'2. XOR Encoding
OPEN "secret2a.dat" FOR OUTPUT AS #1
text$ = "This is my secret message."
key = 123 ' Simple numeric key
FOR i = 1 TO LEN(text$)
PRINT #1, CHR$(ASC(MID$(text$, i, 1)) XOR key);
NEXT
CLOSE #1
'XOR is reversible — use the same key to decode.
OPEN "secret2a.dat" FOR INPUT AS #1
GET #1,1, ch$: ? ch$$
decoded$ = ""
key = 123
WHILE NOT EOF(1)
INPUT #1, ch$ ' : ? ch$
decoded$ = decoded$ + CHR$(ASC(ch$) XOR key) ': ? decoded$
WEND
CLOSE #1
? decoded$
DIALOG NEW 0, "TEST 1", ,, 200, 150, %WS_MINIMIZEBOX+%WS_SYSMENU, 0 TO hDlg
CONTROL ADD LABEL, hDlg, 100, "LABEL 1",80, 40, 60, 14,
CONTROL ADD BUTTON,hDlg, 202, "&Exit Program",100, 100,55, 14, CALL ENDPROG
CONTROL SET FOCUS hDlg, 202
DIALOG SHOW MODAL hDlg TO result
END FUNCTIONThird sample code:
Code:
#COMPILE EXE
#INCLUDE "WIN32API.INC"
GLOBAL hDlg AS LONG
CALLBACK FUNCTION ENDPROG()
DIALOG END CBHNDL, 1
END FUNCTION
FUNCTION PBMAIN () AS LONG
$REGISTER NONE
LOCAL result, i, mask AS LONG
'3. Binary Write with Random Mask
RANDOMIZE TIMER
OPEN "secret 3.dat" FOR BINARY AS #1
text$ = "This is my secret message."
FOR i = 1 TO LEN(text$)
mask = RND(255)
PUT$ #1, CHR$(ASC(MID$(text$, i, 1)) XOR mask)
NEXT
CLOSE #1
OPEN "secret 3.dat" FOR BINARY AS #1
decoded$ = ""
DO UNTIL EOF(1)
GET$ #1, 1, mask1$
GET$ #1, 1, data1$
decoded$ = decoded$ + CHR$(ASC(data1$) XOR ASC(mask1$))
LOOP
CLOSE #1
? decoded$
DIALOG NEW 0, "TEST 1", ,, 200, 150, %WS_MINIMIZEBOX+%WS_SYSMENU, 0 TO hDlg
CONTROL ADD LABEL, hDlg, 100, "LABEL 1",80, 40, 60, 14,
CONTROL ADD BUTTON,hDlg, 202, "&Exit Program",100, 100,55, 14, CALL ENDPROG
CONTROL SET FOCUS hDlg, 202
DIALOG SHOW MODAL hDlg TO result
END FUNCTIONHow to fix?
RE: Making text unreadable, 1 sample code works, 2 do not work - Kurt Kuzba - 23.01.2026
(22.01.2026, 18:32)Robert Alvarez Wrote: Found three code samples in the internet to make text unreadable.
First one can read text and encrypt it and decrypt .
The second and third seems to encrypt it but decrypt does not work.
First sample code:
Code:#COMPILE EXE
#INCLUDE "WIN32API.INC"
GLOBAL hDlg AS LONG
CALLBACK FUNCTION ENDPROG()
DIALOG END CBHNDL, 1
END FUNCTION
FUNCTION PBMAIN () AS LONG
$REGISTER NONE
LOCAL result, i AS LONG
'1. Basic Character Shift (Caesar Cipher Style)
OPEN "secret 1a.dat" FOR OUTPUT AS #1
text$ = "This is my secret message."
FOR i = 1 TO LEN(text$)
PRINT #1, CHR$(ASC(MID$(text$, i, 1)) + 5);
NEXT
CLOSE #1
OPEN "secret 1a.dat" FOR INPUT AS #1: LINE INPUT #1, text$
? text$ 'encryt
FOR i = 1 TO LEN(text$)
text1$=text1$+CHR$(ASC(MID$(text$, i, 1)) - 5)
NEXT
? text1$ 'decreypt
DIALOG NEW 0, "TEST 1", ,, 200, 150, %WS_MINIMIZEBOX+%WS_SYSMENU, 0 TO hDlg
CONTROL ADD LABEL, hDlg, 100, "LABEL 1",80, 40, 60, 14,
CONTROL ADD BUTTON,hDlg, 202, "&Exit Program",100, 100,55, 14, CALL ENDPROG
CONTROL SET FOCUS hDlg, 202
DIALOG SHOW MODAL hDlg TO result
END FUNCTION
Second sample code:
Code:#COMPILE EXE
#INCLUDE "WIN32API.INC"
GLOBAL hDlg AS LONG
CALLBACK FUNCTION ENDPROG()
DIALOG END CBHNDL, 1
END FUNCTION
FUNCTION PBMAIN () AS LONG
$REGISTER NONE
LOCAL result, i, key AS LONG
'2. XOR Encoding
OPEN "secret2a.dat" FOR OUTPUT AS #1
text$ = "This is my secret message."
key = 123 ' Simple numeric key
FOR i = 1 TO LEN(text$)
PRINT #1, CHR$(ASC(MID$(text$, i, 1)) XOR key);
NEXT
CLOSE #1
'XOR is reversible — use the same key to decode.
OPEN "secret2a.dat" FOR INPUT AS #1
GET #1,1, ch$: ? ch$$
decoded$ = ""
key = 123
WHILE NOT EOF(1)
INPUT #1, ch$ ' : ? ch$
decoded$ = decoded$ + CHR$(ASC(ch$) XOR key) ': ? decoded$
WEND
CLOSE #1
? decoded$
DIALOG NEW 0, "TEST 1", ,, 200, 150, %WS_MINIMIZEBOX+%WS_SYSMENU, 0 TO hDlg
CONTROL ADD LABEL, hDlg, 100, "LABEL 1",80, 40, 60, 14,
CONTROL ADD BUTTON,hDlg, 202, "&Exit Program",100, 100,55, 14, CALL ENDPROG
CONTROL SET FOCUS hDlg, 202
DIALOG SHOW MODAL hDlg TO result
END FUNCTION
Third sample code:
Code:#COMPILE EXE
#INCLUDE "WIN32API.INC"
GLOBAL hDlg AS LONG
CALLBACK FUNCTION ENDPROG()
DIALOG END CBHNDL, 1
END FUNCTION
FUNCTION PBMAIN () AS LONG
$REGISTER NONE
LOCAL result, i, mask AS LONG
'3. Binary Write with Random Mask
RANDOMIZE TIMER
OPEN "secret 3.dat" FOR BINARY AS #1
text$ = "This is my secret message."
FOR i = 1 TO LEN(text$)
mask = RND(255)
PUT$ #1, CHR$(ASC(MID$(text$, i, 1)) XOR mask)
NEXT
CLOSE #1
OPEN "secret 3.dat" FOR BINARY AS #1
decoded$ = ""
DO UNTIL EOF(1)
GET$ #1, 1, mask1$
GET$ #1, 1, data1$
decoded$ = decoded$ + CHR$(ASC(data1$) XOR ASC(mask1$))
LOOP
CLOSE #1
? decoded$
DIALOG NEW 0, "TEST 1", ,, 200, 150, %WS_MINIMIZEBOX+%WS_SYSMENU, 0 TO hDlg
CONTROL ADD LABEL, hDlg, 100, "LABEL 1",80, 40, 60, 14,
CONTROL ADD BUTTON,hDlg, 202, "&Exit Program",100, 100,55, 14, CALL ENDPROG
CONTROL SET FOCUS hDlg, 202
DIALOG SHOW MODAL hDlg TO result
END FUNCTION
How to fix?
For that third one, you should have the same randomize at the start of the coding and decoding.
That gives you the same pseudorandom number for the XOR.
For actual encryption, you would have the randomize seed derived from a key word or number.
RE: Making text unreadable, 1 sample code works, 2 do not work - Dale Yarker - 23.01.2026
Was working (unsuccessfully) on second example. I refreshed and saw Kurt's reply. He is 100% correct but mentioned only one of multiple problems.
Patched up third example with comments:
Code:
#compile exe
#dim all '<<==== good idea always
'This is encrypt/decrypt, though with non-secure random
'
'#INCLUDE "WIN32API.INC" '<<=== ??WHY??, no API calls
global hDlg as dword 'Okay, but no reason here
callback function ENDPROG()
if (cb.msg = %wm_command) and (cb.ctlmsg = %bn_clicked) _
and (cb.ctl = 202) then 'left magic number ID
dialog end cbhndl ', 1 not using Result here
end if
end function
function pbmain () as long
''$REGISTER NONE
local result, i as long
local mask as byte 'because each ANSI character is byte sized
local text, decoded, mask1, data1 as string
'3. Binary Write with Random Mask
'RANDOMIZE TIMER 'needs same STARTing mask for code and decode
randomize 123 'extremely weak, testing only
open "secret 3.dat" for binary as #1
text = "This is my secret message." 'text is a PB keyword, but works
for i = 1 to len(text$)
mask = rnd(1, 255)
put$ #1, chr$(asc(mid$(text, i, 1)) xor mask)
next
close #1
randomize 123 'use same seed as code
open "secret 3.dat" for binary as #1
decoded = ""
do until eof(1)
' GET$ #1, 1, mask1 'mask not in file ???????
mask = rnd(1, 255)
get$ #1, 1, data1
decoded = decoded + chr$(asc(data1) xor mask)
loop
close #1
? decoded ,, "After decode."
dialog new 0, "TEST 1", ,, 200, 150, %ws_minimizebox+%ws_sysmenu, 0 to hDlg
control add label, hDlg, 100, "LABEL 1",80, 40, 60, 14,
control add button,hDlg, 202, "&Exit Program",100, 100,55, 14, call ENDPROG
control set focus hDlg, 202
dialog show modal hDlg to result
end functionRE: Making text unreadable, 1 sample code works, 2 do not work - Dale Yarker - 23.01.2026
Code:
'Second Sample
'
'Works more or less now. With fixed key it is coding not encryption.
'Depending on key a character may be a terminating character.
'For example, 123 cuts the message at 22 characters.
'Left in commented out bad code and some of my MSGBOXes.
'Worst was having both GET and INPUT.
'Is this VERY old? ($register none vs #register none)
'Or is it AI generated?
#compile exe
#dim all
#include "WIN32API.INC"
global hDlg as long
callback function ENDPROG()
dialog end cbhndl, 1
end function
function pbmain () as long
'$register none
local result, i as long
local key as byte
local PlainText, ch, chdecoded as string
'2. XOR Encoding
PlainText = "This is my secret message."
open "testSecret2a.dat" for output as #1 len=len(PlainText) chr=ansi
key = 123 ' Simple numeric key
for i = 1 to len(PlainText)
print #1, chr$(asc(mid$(PlainText, i, 1)) xor key); 'MID$ was missing
next
'' seteof #1
close #1
'XOR is reversible — use the same key to decode.
open "testSecret2a.dat" for input as #1
'' get #1, 1, ch
line input #1, ch
'? dec$(len(ch)),, "length of ch after GET"
chdecoded = ""
key = 123
i = 0
''while not eof(1) 'EOF ???? GET or LINE INPUT does file to string
do
chdecoded = chdecoded + chr$(asc(mid$(ch, i, 1)) xor key) '<<<<: ? chdecoded
incr i
''wend
loop until i = len(ch)
close #1
msgbox chdecoded,,"Decoded"
dialog new 0, "TEST 1", ,, 200, 150, %ws_minimizebox+%ws_sysmenu, 0 to hDlg
control add label, hDlg, 100, "LABEL 1",80, 40, 60, 14,
control add button,hDlg, 202, "&Exit Program",100, 100,55, 14, call ENDPROG
control set focus hDlg, 202
dialog show modal hDlg to result
end functionRE: Making text unreadable, 1 sample code works, 2 do not work - Robert Alvarez - 23.01.2026
kurds reply
On the second sample , get one blank msgbox and then a msgbox with "T"?
On the third sample did not get the second msgbox at all. change to ? "xx "+decoded$ and seems to skip this code line?
------
dale y. second sample get ".This is my secret mes" only
dale y. third sample get "This is my secret message. 5"
Have not yet look over dale's code to look for problem.
Yes these sample code were AI generated.
which is best encoder Caesar Cipher, XOR Encoding, or Binary Write with Random Mask
Comparison of Methods:
Binary Write with Random Mask (Best): When the random mask (key) is as long as the message, unique, and kept secret, this method is fundamentally unbreakable. It is essentially a One-Time Pad.
XOR Encoding (Moderate/Weak): Offers speed and simplicity. If used with a single-byte or repeating key, it is easily broken. It is commonly used in malware for simple obfuscation.
Caesar Cipher (Worst): A basic substitution cipher with only 25 possible keys (in English), making it trivial to break with modern computing.
For high-security needs, the random mask approach is superior, whereas Caesar and basic XOR are generally for educational purposes or, at best, lightweight obfuscation.
do not know what "One-Time Pad." in Binary Write means. Looking for code to reuse again and again , not one time.?
RE: Making text unreadable, 1 sample code works, 2 do not work - Dale Yarker - 24.01.2026
Quote:dale y. second sample get ".This is my secret mes" onlyNoted in code opening comments. Try a different key. (note key needs changing in 2 places)
Quote:dale y. third sample get "This is my secret message. 5"changing the seed to RANDOMIZE, changes the "extra" character.
The dot dat file has one character too many. I don't see how.
Quote: It is essentially a One-Time Pad.No it isn't. It is key stream.
Both 2 and 3 are XOR. One with a single fixed modifier value (VERY unsecure), the other with a stream from a PRNG. note: RND is not a cryptographically secure PRNG.
RE: Making text unreadable, 1 sample code works, 2 do not work - Robert Alvarez - 25.01.2026
The most famous and commonly used "big" number for a Caesar cipher is
13 (often referred to as ROT13).
Here is a breakdown of key numbers associated with the Caesar Cipher:
13 (ROT13): This is the most common variant because it is self-decoding. Shifting the alphabet by 13 places twice brings you back to the original text (13 + 13 = 26).
3: Historically, Julius Caesar himself is reported to have used a shift of 3.
1–25: The Caesar cipher is a "shift cipher" that can use any integer shift from 1 to 25, as there are only 25 possible functional shifts in the 26-letter English alphabet.
26 (Base): While not a shift amount, 26 is the modulo base, meaning a shift of 26 is the same as a shift of 0 (no change), and a shift of 27 is the same as a shift of 1.
For maximum obfuscation while remaining a "Caesar Style" cipher, 13 is the standard, popular choice
RE: Making text unreadable, 1 sample code works, 2 do not work - Dale Yarker - 26.01.2026
1. ???????????????????????? what is the objective?
2. 13 being most obvious makes it most likely to try first.
RE: Making text unreadable, 1 sample code works, 2 do not work - Robert Alvarez - 26.01.2026
Just comments from web AI about Caesar cipher