RE: [PHP] Maths not working.. or is it me?
| From: | Hawkes, Richard | Date: | Thu, 15 Apr 2004 10:10:52 +0000 |
| Subject: | RE: [PHP] Maths not working.. or is it me? | ||
| Groups: | php.general | ||
| Request: | Send a blank email to php-general+get-183431@lists.php.net to get a copy of this message | ||
I don't know what you're doing wrong... But why not use base64_encode/decode,
if all you're worried about is not storing the details in plain text...
-----Original Message-----
From: Tristan.Pretty@risk.sungard.com
[mailto:Tristan.Pretty@risk.sungard.com]
Sent: 15 April 2004 10:59
To: php-general@lists.php.net
Subject: [PHP] Maths not working.. or is it me?
Im trying to implement some really simply credit card encryption...
I know it's not perfect, but it's a stop gap measure until I do this
properly... however...
To Encrypt before I put into my DB, I'm using this formula...
$encrypt = $CardNumber / ($ExpiryYear * 41.9);
(41.9 is just a random No to help encrpt the data)
To see the correct credit card No later, I'm using this formula:
$decrypt = $row[encryptedno] * $row[expiryyear] * 41.9;
The credit car No I'm testing with is:
1234123412341234
and the Exp year is 2008
However, I keep getting this result...
1.2341234123412E+15
What on earth am I doing wrong?
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