登入界面
<?php
session_start();
header('Content-type:text/html;charset=utf-8');
if(isset($_SESSION['username']) && $_SESSION['username']==='zeng'){
exit('您已经登入了，请不要重新登入');
}
if(isset($_POST['submit'])){
if(isset($_POST['username']) && isset($_POST['password']) && $_POST['username']=='zeng' && $_POST['password']=='123456' ){
$_SESSION['username']=$_POST['username'];
header('location:skip.php?url=index.php&info=登入成功！3秒后跳转到首面');
} else {
header('location:skip.php?url=login.php&info=对不起，用户名活密码填写错误！3秒后跳转到登入页面');
}
}
?>
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="utf-8">
<title>请登入</title>
</head>
<body>
<form method="post" action="">
姓名：<input type="text" name="username" />
密码：<input type="password" name="password"/>
<input type="submit" name="submit" value="登入"/>
</form>
</body>
</html>
跳转处理页面skip.php
<?php
if(!isset($_GET['url']) || !isset($_GET['info'])){
exit();
}
?>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="refresh" content="3,URL=<?php echo $_GET['url'] ?>"/>
<title>正在跳转中...</title>
</head>
<body>
<div><?php echo $_GET['info'] ?></div>
</body>
</html>
登入首页index.php
<?php
session_start();
header('Content-type:text/html;charset=utf-8');
if(isset($_SESSION['username']) && $_SESSION['username']==='zeng'){
echo "您好！{$_SESSION['username']},欢迎回来！";
echo "<a href='logout.php'>注销</a>";
} else {
echo "<a href='login.php'>请登入</a>";
}
?>
注销处理界面logout.php
<?php
session_start();
header('Content-type:text/html;charset=utf-8');
if(isset($_SESSION['username']) && $_SESSION['username']==='zeng'){
session_unset();//free all session variable
session_destroy();//销毁一个会话中的全部数据
setcookie(session_name(),'',time()-3600);//销毁与客户端的卡号
header('location:skip.php?url=index.php&info=注销成功，正在跳转！');
}else{
header('location:skip.php?url=index.php&info=注销失败，请稍后重试！');
}
?>