function encrypt($id){
  $id=serialize($id);
  $key="1112121212121212121212";
  $data['iv']=base64_encode(substr('fdakinel;injajdji',0,16));
  $data['value']=openssl_encrypt($id, 'AES-256-CBC',$key,0,base64_decode($data['iv']));
  $encrypt=base64_encode(json_encode($data));
  return $encrypt;
}

function decrypt($encrypt)
{
  $key = '1112121212121212121212';//解密钥匙
  $encrypt = json_decode(base64_decode($encrypt), true);
  $iv = base64_decode($encrypt['iv']);
  $decrypt = openssl_decrypt($encrypt['value'], 'AES-256-CBC', $key, 0, $iv);
  $id = unserialize($decrypt);
  if($id){
    return $id;
  }else{
    return 0;
  }
}