<?php 
include "conn.php";
$id = $_GET["id"];
$sql = "delete from mess where m_id=".$id;
//执行
$res=$mysqli->query($sql);
if($res){
//跳转页面
echo "<script type='text/javascript'>alert('留言删除成功，正在跳转到显示留言页面');location='showly.php';</script>";
}
else
{
echo "删除失败！";
}?>