Making text unreadable, 1 sample code works, 2 do not work

[Robert Alvarez]

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?