所以我设计了一个登录系统。但是,当用户登录时,我将他重定向到一个有菜单的新页面。但是,当用户注销并复制主页URL时。他有能力再次回来。我如何防止这种情况?防止用户输入一次注销
的login.php
<html>
<head>
<title>Log in</title>
</head>
<body>
<h1>Welcome please sign in!</h1>
<?php if (!isset($_POST[ 'submit'])){ ?>
<!-- The HTML login form -->
<form action="<?=$_SERVER['PHP_SELF']?>" method="post">
Username:
<input type="text" name="username" />
<br />Password:
<input type="password" name="password" />
<br />
<input type="submit" name="submit" value="Login" />
</form>
<?php } else { require_once("db_const.php"); $mysqli=n ew mysqli(DB_HOST, DB_USER, DB_PASS, DB_NAME); # check connection if ($mysqli->connect_errno) { echo "
<p>MySQL error no {$mysqli->connect_errno} : {$mysqli->connect_error}</p>"; exit(); } $username = $_POST['username']; $password = $_POST['password']; $sql = "SELECT * from users WHERE username LIKE '{$username}' AND password LIKE '{$password}' LIMIT 1";
$result = $mysqli->query($sql); if (!$result->num_rows == 1) { echo "
<p>Invalid username/password combination</p>"; } else { echo '
<script language="javascript">
';
\t \t echo '
alert("Log in successfull!")
';
\t \t echo '
</script>'; header("refresh:5;url=home.php"); } } ?>
</body>
</html>
注销:
<?php
session_start();
session_destroy();
header('Location: login.php');
exit;
?>
和菜单页:
<a href="login.php">Logout</a>
这不是php的工作方式! –
你在会话中存储什么? – Virb
了解如何使用PHP。 :) –