/**
* 加密
*/
function lock_param($content,$key='')
{
$content = $content . $key;
$chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-=+";
$nh = rand(0, 64);
$ch = $chars[$nh];
$mdKey = md5($key . $ch);
$mdKey = substr($mdKey, $nh % 8, $nh % 8 + 7);
$content = base64_encode($content);
$tmp = '';
$i = 0;
$j = 0;
$k = 0;
for ($i = 0; $i < strlen($content); $i++) {
$k = $k == strlen($mdKey) ? 0 : $k;
$j = ($nh + strpos($chars, $content[$i]) + ord($mdKey[$k++])) % 64;
$tmp .= $chars[$j];
}
return urlencode(base64_encode($ch . $tmp));
}
/**
* 解密
*/
function unlock_param($content,$key=''){
$content = base64_decode(urldecode($content));
$chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-=+";
$ch = $content[0];
$nh = strpos($chars,$ch);
$mdKey = md5($key.$ch);
$mdKey = substr($mdKey,$nh%8, $nh%8+7);
$content = substr($content,1);
$tmp = '';
$i=0;$j=0; $k = 0;
for ($i=0; $i<strlen($content); $i++) {
$k = $k == strlen($mdKey) ? 0 : $k;
$j = strpos($chars,$content[$i])-$nh - ord($mdKey[$k++]);
while ($j<0) $j+=64;
$tmp .= $chars[$j];
}
return trim(base64_decode($tmp),$key);
}