给定可用的字符列表生成一个指定长度的随机字符串
<?
function randomString($len) {
srand(date("s"));
$possible="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890!@#$%^&*()";
$str="";
while(strlen($str)<$len) {
$str.=substr($possible,(rand()%(strlen($possible))),1);
}
return($str);
}
?>
