cookie与session实战-2019年11月22日

SESSION 登录实战

index首页文件

<?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>

check登录验证

<?php
require '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';
}

logout退出

<?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>';
}