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Correction status：qualified
Teacher's comments：业务逻辑是正确的, 如果让你自己写, 能否写出来呢?
Collection
Collection
<?php
//cookie
//if (isset($_COOKIE['username']) && $_COOKIE['username'] === 'admin') {
// echo '用户: ' . $_COOKIE['username'] . '已登录<br>';
// echo '<a href="dispatch.php?action=logout">退出</a>';
//} else {
// // 未登陆跳到登陆页面
// echo '<a href="dispatch.php?action=login">请登录</a>';
//}
//session part
session_start();
if (isset($_SESSION['username']) && $_SESSION['username'] === 'admin') {
echo '用户: ' . $_SESSION['username'] . '已登录<br>';
echo '<a href="dispatch.php?action=logout">退出</a>';
} else {
//未登陆跳到登陆页面
echo '<a href="dispatch.php?action=login">请登录</a>';
}点击 "运行实例" 按钮查看在线实例
<?php
// 请求派发器: 前端控制器
// 功能就是获取到用户的请求, 并调用不同的脚本进行处理和响应
require __DIR__ . '/db/connect.php';
//判断请求的值
$action = isset($_GET[ 'action' ]) ? $_GET[ 'action' ] : 'login';
// htmlentites ->转换成html
//strtolower-> 转换在小写
//trim-> 删除空格
$action = htmlentities(strtolower(trim($action)));
//分发请求
switch ($action) {
//获取参数login -> 跳到login页面
case 'login':
include __DIR__ . '/login.php';
break;
//获取参数check -> 跳到check页面
case 'check':
include __DIR__ . '/check.php';
break;
//获取参数logout -> 跳到logout页面
case 'logout':
include __DIR__ . '/logout.php';
break;
default:
header('Location : index.php');
// JS : echo '<script>location.assign("index.php");</script>';
}点击 "运行实例" 按钮查看在线实例
<?php
//cookie 部分
//if (isset($_COOKIE['username']) && $_COOKIE['username'] === 'admin') {
// echo '<script>alert("你已登陆");location.assign("index.php");</script>';
//}
//session 部分
session_start();//开启session
if (isset($_SESSION['username']) && $_SESSION['username'] === 'admin') {
echo '<script>alert("你已登录");location.assign("index.php");</script>';
}
?>
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>用户登录</title>
</head>
<body>
<h3>用户登录</h3>
<!--action=check: 跳转登录时进行验证-->
<!--return isEmpty(): 利用function获取状态 true:成功 / false:失败-->
<form action="dispatch.php?action=check" method="post" onsubmit="return isEmpty();"
<p>
<label for="email">邮箱:</label>
<input type="email" name="email" id="email">
</p>
<p>
<label for="password">密码:</label>
<input type="password" name="password" id="password">
</p>
<p>
<button>提交</button>
</p>
</form>
<script>
//检查用户输入是否为空
function isEmpty() {
var emailValue = document.querySelector('#email').value;
var passwordValue = document.querySelector('#password').value;
if(emailValue.length === 0 || passwordValue.length === 0){
alert('邮箱或者密码没有输入!');
//返回值为false 提交事件失敗
return false;
}
}
</script>
</body>
</html>点击 "运行实例" 按钮查看在线实例
<?php
session_start();
//判断请求类型
if ( $_SERVER[ 'REQUEST_METHOD' ] === 'POST' ) {
$email = $_POST[ 'email' ];
//sha1 加密方法，也可用md5
$password = sha1($_POST[ 'password' ]);
//与database验证
$sql = 'SELECT * FROM `user` WHERE `email`=:email AND `password`=:password LIMIT 1';
$preObj = $pdo->prepare($sql);
//执行 -> 从$_POST获取的值,在SQL中查询
$preObj->execute([ 'email' => $email , 'password' => $password ]);
//返回数据
$user = $preObj->fetch(PDO::FETCH_ASSOC);
if ( $user === false ) {
//database验证失败 返回上一页
echo '<script>alert("验证失败!");history.back();</script>';
exit();
}
//cookie用法
// setcookie('username' , $user[ 'username' ]);
//Session用法
$_SESSION['username'] = $user['username'];
echo '<script>alert("登陆成功");location.assign("index.php");</script>';
exit;
} else {
die('请求失败');
}点击 "运行实例" 按钮查看在线实例
<?php
// 必须在用户已经登录的情况下再退出
//cookie有值 = 已登入
//cookie 部分
//if ( isset($_COOKIE[ 'username' ]) && $_COOKIE[ 'username' ] === 'admin' ) {
// //清空cookie -> logout
// setcookie('username' , null , time() - 3600); 也可自行设置时间不一定要3600 S
// echo '<script>alert("退出成功");location.assign("index.php");</script>';
//} else {
// echo '<script>alert("请登录");location.assign("login.php");</script>';
//}
//session 部分
session_start();
if ( isset($_SESSION[ 'username' ]) && $_SESSION[ 'username' ] === 'admin' ) {
//unset session => logout
session_unset();
setcookie('PHPSESSID' , null , time() - 3600);
echo '<script>alert("退出成功");location.assign("index.php");</script>';
} else {
// 要求用户登录
echo '<script>alert("请登录");location.assign("login.php");</script>';
}点击 "运行实例" 按钮查看在线实例
