如何在单个表单中实现封面图片与多张照片的上传

<form method="post" enctype="multipart/form-data">
  <label for="cover-input">选择相册封面</label>
  <input type="file" name="cover" id="cover-input" accept="image/*">

  <label for="photos-input">选择多张照片</label>
  <input type="file" name="photos[]" id="photos-input" multiple accept="image/*">

  <label for="album-name-input">相册名称</label>
  <input type="text" name="nameAlbum" id="album-name-input" placeholder="输入相册名称"/>

  <button type="submit">提交</button>
</form>

form{
  background-color: #eee;
  border-radius: 20px;
  display: flex;
  flex-direction: column;
  gap: 15px;
  margin: 0 auto;
  padding: 20px;
  width: 400px;
}

form button{
  background-color: crimson;
  border: none;
  color: #fff;
  padding: 10px;
  cursor: pointer;
}
form input[type="text"], form input[type="file"]{
  padding: 7px 10px;
  border: 1px solid #ccc;
  border-radius: 5px;
}

<?php
// 1. 数据库配置
$dbHost = 'localhost';
$dbName = 'your_database_name';
$dbUser = 'your_username';
$dbPass = 'your_password';

// 2. 文件上传目录
$uploadDir = 'uploads/'; // 确保此目录存在且PHP有写入权限

// 确保上传目录存在
if (!is_dir($uploadDir)) {
    mkdir($uploadDir, 0777, true);
}

// 数据库连接
try {
    $conn = new PDO("mysql:host=$dbHost;dbname=$dbName;charset=utf8", $dbUser, $dbPass);
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    // echo "数据库连接成功！"; // 调试用
} catch (PDOException $e) {
    die("数据库连接失败: " . $e->getMessage());
}

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $albumName = trim($_POST['nameAlbum']);
    $coverPath = null;
    $photoPaths = [];

    // 3. 验证相册名称
    if (empty($albumName)) {
        echo "相册名称不能为空！";
        exit;
    }

    // 4. 处理封面图片上传
    if (isset($_FILES['cover']) && $_FILES['cover']['error'] === UPLOAD_ERR_OK) {
        $coverTmpName = $_FILES['cover']['tmp_name'];
        $coverFileName = basename($_FILES['cover']['name']);
        $coverTargetFile = $uploadDir . uniqid() . '_' . $coverFileName; // 使用uniqid防止文件名冲突

        if (move_uploaded_file($coverTmpName, $coverTargetFile)) {
            $coverPath = $coverTargetFile;
            // echo "封面图片上传成功: " . $coverPath . "<br>"; // 调试用
        } else {
            echo "封面图片上传失败！<br>";
        }
    } else if (isset($_FILES['cover']) && $_FILES['cover']['error'] !== UPLOAD_ERR_NO_FILE) {
        echo "封面图片上传错误: " . $_FILES['cover']['error'] . "<br>";
    }

    // 5. 处理多张照片上传
    if (isset($_FILES['photos'])) {
        $totalPhotos = count($_FILES['photos']['name']);
        for ($i = 0; $i < $totalPhotos; $i++) {
            if ($_FILES['photos']['error'][$i] === UPLOAD_ERR_OK) {
                $photoTmpName = $_FILES['photos']['tmp_name'][$i];
                $photoFileName = basename($_FILES['photos']['name'][$i]);
                $photoTargetFile = $uploadDir . uniqid() . '_' . $photoFileName;

                if (move_uploaded_file($photoTmpName, $photoTargetFile)) {
                    $photoPaths[] = $photoTargetFile;
                    // echo "照片上传成功: " . $photoTargetFile . "<br>"; // 调试用
                } else {
                    echo "照片上传失败: " . $photoFileName . "<br>";
                }
            } else if ($_FILES['photos']['error'][$i] !== UPLOAD_ERR_NO_FILE) {
                echo "照片上传错误 (" . $photoFileName . "): " . $_FILES['photos']['error'][$i] . "<br>";
            }
        }
    }

    // 6. 将数据存储到数据库
    if ($albumName) {
        try {
            // 假设有一个 albums 表来存储相册信息
            $stmtAlbum = $conn->prepare("INSERT INTO albums (name, cover_path) VALUES (?, ?)");
            $stmtAlbum->execute([$albumName, $coverPath]);
            $albumId = $conn->lastInsertId(); // 获取新插入的相册ID

            if ($albumId && !empty($photoPaths)) {
                // 假设有一个 album_photos 表来存储相册内的照片
                $stmtPhotos = $conn->prepare("INSERT INTO album_photos (album_id, photo_path) VALUES (?, ?)");
                foreach ($photoPaths as $path) {
                    $stmtPhotos->execute([$albumId, $path]);
                }
                echo "相册 '" . htmlspecialchars($albumName) . "' 及其照片已成功上传并保存！";
            } else if ($albumId) {
                 echo "相册 '" . htmlspecialchars($albumName) . "' (无附加照片) 已成功上传并保存！";
            } else {
                 echo "相册信息保存失败！";
            }

        } catch (PDOException $e) {
            echo "数据库操作失败: " . $e->getMessage();
            // 可以在这里回滚事务，删除已上传的文件等
        }
    }
}
?>

-- albums 表
CREATE TABLE `albums` (
  `id` INT AUTO_INCREMENT PRIMARY KEY,
  `name` VARCHAR(255) NOT NULL,
  `cover_path` VARCHAR(255) DEFAULT NULL,
  `created_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

-- album_photos 表
CREATE TABLE `album_photos` (
  `id` INT AUTO_INCREMENT PRIMARY KEY,
  `album_id` INT NOT NULL,
  `photo_path` VARCHAR(255) NOT NULL,
  `uploaded_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
  FOREIGN KEY (`album_id`) REFERENCES `albums`(`id`) ON DELETE CASCADE
);