We help IT Professionals succeed at work.

# How to encrypt and descrypt txt file

on
I have a txt format file and don't like user to use Notepad to view it, how to encrypt it and descrypt it?

Thanks

Shekou
Comment
Watch Question

## View Solution Only

Software Developer
CERTIFIED EXPERT

Commented:
http://www.torry.net/cryptstrong.htm

Commented:
There are diffrent way's to do i. the most smple one is to do an xor "encryption" you encrypt byte per byte with eg. 56.. now the file is encrypted to decrypt it xor with  56 again and the original text will appear.

look for this on the web

blowfish
des

this will lead to manny good sites..

happy hunting!

Commented:
Hello Shekou,

there are many encyption methods

http://www.efg2.com/Lab/Library/Delphi/MathFunctions/Cryptography.htm

Best Regards

Cesario

Commented:
This works fine for both cryptin and decrypting

procedure Scrample(var fin, fout : Text);
var
ch : char;
begin
randseed := 12345;  // Your code;
While not eof(fin) do begin
ch := char(random(256) xor byte(ch));
write(fout,ch);
end;
end;

You have to open and close the files self !

Olle K
Commented:
I made a simple function that takes a line as input and encrypts it or decrypts it.

function MyIncrypt(Fcode: Boolean; FTextIn : string): string;
var MyChar   : char;
MyString : String;
i , key  : integer;
begin
Result := '';
key := length(FTextIn);

if FCode then //Encrypt
begin
for i := 1 to key do
begin
MyString  := copy(FTextIn, i, 1);
MyChar := char( Ord(MyString[1]) + key + i + FKeyValue mod   256);
Result := Result + chr(Ord(MyChar))
end;
end else //Decrypt
begin
for i := 1 to key do
begin
MyString  := copy(FTextIn, i, 1);
MyChar := char( Ord(MyString[1]) - key - i - FKeyValue mod   256);
Result := Result + chr(Ord(MyChar))
end;
end;
end;

Marcel (Holland)

Commented:
Work great!

Thanks

Shekou