<center>
<?php
include("conn.php");
$name=$_POST['username'];
$passowrd=$_POST['password'];
$sql = "SELECT * from user WHERE username = '$name' and password='$passowrd'";
$res = mysql_query($sql);
$rows=mysql_num_rows($res);
if($rows){
setcookie("cookie", "ok");
header("refresh:0;url=list.php");
exit;
}
else echo " <script language=javascript>alert('用户名密码错误');history.back(); </script>";
include("head.php");
if($_COOKIE['cookie']!='ok'){
?>
<form action="" method="post" name="myform" onsubmit="return Checklogin();">
ID： <input type="text" name="username" /> <br>
PW： <input type="password" name="password" /> <input type="submit" name="submit" value="登陆"/>
</form>
<?
}else{
?>
<a href='?out=login'>退出 </a>
<?
}
?>
</center>
这是我的一个登录界面的代码，但是问题是每次一刷新就自动的弹出 用户名密码错误的�
