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查无此人Correction status：qualified
Teacher's comments：完成的不错，继续加油。
Collection
Collection
<?php// 开启session会话session_start();// 判断用户是否登录，如果没有，则跳转到相应的页面// var_dump($_SESSION['name']);// die;if (isset($_SESSION['name'])) {echo '用户: ' . $_SESSION['name'] . '已登录<br>';echo '<a href="logout.php">退出</a>';} else {// 2. 未登录,就跳转到登录页面echo '<a href="login.php">请登录</a>';}
<?php// 防止用户重复登录if (isset($_SESSION['name'])) {session_start();# code...echo '<script>alert("不要重复登录");location.assign("index.php");</script>';}?><!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta http-equiv="X-UA-Compatible" content="ie=edge"><title>登录</title></head><body><h3>用户登录</h3><form action="check.php" method="post" onsubmit="return isEmpty();"><p><label for=" phone">手机:</label><input type="phone" name="phone" id="phone"></p><p><label for="password">密码:</label><input type="password" name="password" id="password"></p><p><button>提交</button></p></form><script>function isEmpty() {var phone = document.getElementById('phone').value;var password = document.getElementById('password').value;if (phone.length === 0 || password.length === 0) {alert('手机和密码不能为空');return false;}}</script></body></html>
<?phprequire 'connect.php';session_start();// 1.判断用户的请求类型是否正确?if ($_SERVER['REQUEST_METHOD'] === 'POST') {// 获取表单提交的数据$user_name = $_POST['phone'];$user_alias = md5($_POST['password']);// var_dump($user_alias);// die;// 3. 用用户表user.dbf进行验证$sql = 'SELECT * FROM `user` WHERE `phone` = :phone AND `pwd` = :password LIMIT 1';$stmt = $pdo->prepare($sql);$stmt->execute(['phone' => $user_name, 'password' => $user_alias]);$user = $stmt->fetch(PDO::FETCH_ASSOC);// var_dump($user['name']);// die;// 4. 判断验证的结果if (false === $user) {// 验证失败,返回上一下页面echo '<script>alert("验证失败");history.back();</script>';die;}// 验证成功，将用户的信息写到session$_SESSION['name'] = $user['name'];// var_dump($_SESSION['name']);// die;echo '<script>alert("登录成功");location.assign("index.php");</script>';exit;} else {echo '请求类型错误';}
<?php// 必须在用户已经登录的情况下再退出session_start();if (isset($_SESSION['name'])) {session_destroy();echo '<script>alert("退出成功");location.assign("index.php");</script>';} else {// 要求用户先登录echo '<script>alert("请先登录");location.assign("login.php");</script>';}
数据库：
登录前
用户登录页
验证页
登录成功页
cookie与session提供两个页面通信，他们在在多个页面存储一些公共变量，每个页面都能访问这些
变量，实现多个页面的通信作用。
cookie的数据存于客户端，session的数据一般存于服务端。
