來源：下載的 ? ? ? ?mysqli\mooc mysqli\mysqli\imoocComment

彈出

?warning：Notice: Undefined variable: comments in D:\wamp\www\text trt\mysqli\mooc mysqli\mysqli\imoocComment\index.php on line?23

源碼：

-------------------------------------------

<?php?

foreach($comments as $val){

echo $val->output();

}

?>

-------------------------------------------

請問是為什么？