添加文章时用代码如下：
<select name="NClass" id="NClass" class="sel">
<?php
$querySel = "select * from nclass";
$result_sub = mysql_query($querySel) or die(mysql_error());
$i = 0;
while($row_sub=mysql_fetch_array($result_sub))
{
$result_show[$i] = $row_sub;
echo "<option value='". $result_show[$i]['ID'] ."'>". $result_show[$i]['ClassName'] ."</option>";
$i++;
}
?>
</select>
<select name="NClass"
