<?PHP function create_GUId(){
$charid = strtoupper(md5(uniqid(mt_rand(), true)));
$uuid = substr($charid, 0, 8).'-'.substr($charid, 8, 4).'-'
.substr($charid,12, 4).'-'.substr($charid,16, 4).'-'
.substr($charid,20,12);
return $uuid;
} ?>可以生成全球唯一不会重复的UUID序号。