<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
<title>IBAN berechnen</title>
<style type="text/css">
table.content{font-family:tahoma,arial,sans-serif;font-size:12px;font-weight:normal;text-align:center;color:#000066;}
</style>
</head>
<body>
<form action="<?php $_SERVER['PHP_SELF'] ?>" method="POST">
<table border="0" class="content">
<tr>
<td><div align="right"><label for="kto">Kontonummer:</label></td>
<td>
<input id="kto" type="text" name="kto"<?php if(isset($_REQUEST['kto'])) echo " value=\"".$_REQUEST['kto']."\"" ?> style="font-weight:normal;height:17px;width:140px;background-color:#FFFFFF;color:black;font-size:13px;border:solid 1px #505050">
</td>
</tr>
<tr>
<td><div align="right"><label for="blz">BLZ:</label></td>
<td>
<input id="blz" type="text" name="blz"<?php if(isset($_REQUEST['blz'])) echo " value=\"".$_REQUEST['blz']."\"" ?> style="font-weight:normal;height:17px;width:140px;background-color:#FFFFFF;color:black;font-size:13px;border:solid 1px #505050">
</td>
</tr>
<tr>
<td></td>
<td>
<input id="country_str" type="hidden" name="country_str" value="<?php echo (isset($_REQUEST['kto'])) ? $_REQUEST['country_str'] : "DE"; ?>">
<input type="submit" value="IBAN berechnen" style="background-color='#D4D0C8';font-family:verdana,arial;font-size:11px;width:145px;height:22px;border:solid 1px;margin-bottom:20px" onmouseover="this.style.backgroundColor='#404040';this.style.color='#FFFFFF';" onmouseout="this.style.backgroundColor='#D4D0C8';this.style.color='#000000';"/>
</td>
</tr>
</table>
</form>
<?php
if(isset($_REQUEST['kto'], $_REQUEST['blz'], $_REQUEST['country_str']) && (!is_numeric($_REQUEST['kto']) || !is_numeric($_REQUEST['blz']) || (strlen($_REQUEST['country_str']) != 2))) die("<table class='content' style='color:red;font-size:18px'><tr><td><strong>Ungültige Angaben!</strong></td></tr></table>");
$kto = $_REQUEST['kto'];
$blz = $_REQUEST['blz'];
$country_str = strtoupper($_REQUEST['country_str']);
$iban = $country_str . str_pad(98-intval(bcmod(str_pad($blz, 8, "0", STR_PAD_LEFT).str_pad($kto, 10, "0", STR_PAD_LEFT) . strval(ord(substr($country_str, 0, 1)) - 55).strval(ord(substr($country_str, 1, 1)) - 55)."00", "97")), 2, "0", STR_PAD_LEFT) . str_pad($blz, 8, "0", STR_PAD_LEFT).str_pad($kto, 10, "0", STR_PAD_LEFT);
if($iban == "98000000000000000000")
{$iban = "Kontonummer und Bankleizahl eingeben!";}
else
{$iban = "Die IBAN lautet: ".$iban;}
echo '<table border="0" class="content" style="font-size:18px"><tr><td></td><td><strong>'.$iban.'</strong></td></tr></table>';
?>
</body>
</html>
