您现在的位置：程式碼之家 >> 編程語言 > >> 網頁程式設計 >> PHP 程式設計 >> PHP 綜合知識

PHP 分頁功能完整實作：從邏輯原理到可複用程式碼

編輯：PHP 綜合知識

分頁核心參數

$totalRows：總資料筆數
$pageSize：每頁顯示筆數
$currentPage：目前頁碼（從 $_GET 取得）
$totalPages：總頁數 = ceil($totalRows / $pageSize)
$offset：資料庫 OFFSET = ($currentPage - 1) * $pageSize

完整分頁類別實作

<?php
class Paginator {
    private int $totalRows;
    private int $pageSize;
    private int $currentPage;
    private int $totalPages;
    private string $urlPattern; // 如 '/list?page={page}'

    public function __construct(int $totalRows, int $pageSize = 20, string $urlPattern = '') {
        $this->totalRows = max(0, $totalRows);
        $this->pageSize = max(1, $pageSize);
        $this->totalPages = (int)ceil($this->totalRows / $this->pageSize);
        $this->currentPage = $this->normalizePage((int)($_GET['page'] ?? 1));
        $this->urlPattern = $urlPattern ?: $this->detectUrlPattern();
    }

    private function normalizePage(int $page): int {
        return max(1, min($page, $this->totalPages ?: 1));
    }

    private function detectUrlPattern(): string {
        $base = rtrim($_SERVER['SCRIPT_NAME'], '/');
        $query = $_GET;
        unset($query['page']);
        $qs = $query ? '?' . http_build_query($query) : '';
        return $base . $qs . ($query ? '&' : '?') . 'page={page}';
    }

    public function getOffset(): int {
        return ($this->currentPage - 1) * $this->pageSize;
    }

    public function getLimit(): string {
        return "LIMIT {$this->getOffset()}, {$this->pageSize}";
    }

    public function getPageRange(int $displayCount = 9): array {
        $half = (int)floor($displayCount / 2);
        $start = max(1, $this->currentPage - $half);
        $end = min($this->totalPages, $start + $displayCount - 1);
        $start = max(1, $end - $displayCount + 1);
        return range($start, $end);
    }

    public function render(): string {
        if ($this->totalPages <= 1) return '';

        $html = '<nav aria-label="Pagination"><ul class="pagination">';

        // 首頁、上一頁
        if ($this->currentPage > 1) {
            $html .= $this->link(1, '« 首頁');
            $html .= $this->link($this->currentPage - 1, '‹ 上一頁');
        }

        // 頁碼區間
        foreach ($this->getPageRange() as $page) {
            $html .= $page === $this->currentPage
                ? "<li class=\"active\"><span>{$page}</span></li>"
                : $this->link($page, (string)$page);
        }

        // 下一頁、尾頁
        if ($this->currentPage < $this->totalPages) {
            $html .= $this->link($this->currentPage + 1, '下一頁 ›');
            $html .= $this->link($this->totalPages, '尾頁 »');
        }

        $html .= '</ul></nav>';
        return $html;
    }

    private function link(int $page, string $text): string {
        $url = str_replace('{page}', $page, $this->urlPattern);
        return "<li><a href=\"{$url}\">{$text}</a></li>";
    }

    // 取得分頁資訊陣列，供 API 回傳
    public function toArray(): array {
        return [
            'current_page' => $this->currentPage,
            'per_page' => $this->pageSize,
            'total_pages' => $this->totalPages,
            'total_rows' => $this->totalRows,
            'offset' => $this->getOffset(),
        ];
    }
}

使用範例

<?php
// 1. 取得總筆數
$pdo = new PDO($dsn, $user, $pass);
$total = $pdo->query("SELECT COUNT(*) FROM articles WHERE status=1")->fetchColumn();

// 2. 實例化分頁器
$pager = new Paginator($total, 15);

// 3. 查詢當頁資料
$stmt = $pdo->prepare("SELECT * FROM articles WHERE status=1 ORDER BY id DESC " . $pager->getLimit());
$stmt->execute();
$articles = $stmt->fetchAll(PDO::FETCH_ASSOC);

// 4. 輸出分頁導航
echo $pager->render();

// API 模式回傳 JSON
// echo json_encode(['data' => $articles, 'pagination' => $pager->toArray()]);