如何从 WordPress 帖子图像生成 PDF？

如何解决如何从 WordPress 帖子图像生成 PDF？

我正在尝试向自定义帖子类型单页添加一个按钮，然后单击该按钮后，它应该能够生成包含帖子内图像的 PDF。我正在使用自定义主题，我想出了一个接近的解决方案，但出了点问题，我真的不知道如何正确地做到这一点。

这就是我在前端添加按钮的方式。

这是我使用过的按钮代码，我在 name 属性中使用了 me_post_pdf 函数。

<form method="POST">
<input type="submit" value="Download" class="btn1">
<input type="hidden" name="me_post_pdf" value="submitted">
</form>

在我的自定义插件functions.php文件中

use Dompdf\Dompdf;
use Dompdf\Options;


class MyPlugin {
    private $postId;

    public function __construct($wp_query) {
        if ($wp_query && $wp_query->post) {
            $this->postId = $wp_query->post->ID;
        }
    }

    public function getPostId() {
        return $this->postId;
    }

    public function get_car_photos( $post_id,$post_type ){
        global $wpdb;
        $photos = $wpdb->get_results( "SELECT * FROM wp_wj_photos WHERE post_id =  $post_id and post_type = '$post_type' and is_delete = 0 ORDER BY is_main DESC");
        $photos = json_decode(json_encode($photos),true);
        foreach ($photos as $key => &$photo) {
            $photo['photo_url'] = AT_UPLOAD_URI_THEME . '/' . $post_type . '/' . sprintf('%02s',substr( $photo['id'],-2,2) ) . '/';
            $photo['photo_name'] = $photo['id'] . '.jpg';
        }
        return $photos;
    }

    public function add_button() {
        echo '<form method="POST">';
        echo '<input type="submit" value="Download" class="btn1">';
        echo '<input type="hidden" name="me_post_pdf" value="submitted">';
        echo '</form>';
    }

    public function process_pdf($content) {
        global $wp;
        $options = new Options();

        global $wp_query;
        $myPlugin = new MyPlugin($wp_query);

        $options->set('isRemoteEnabled',true);
        $dompdf = new Dompdf($options);

        foreach ($content as $key => $con) {
            $html = '<img src="'.$con['photo_url'].'original/'.$con['photo_name'].'" alt="" height="100%" width="100%">';
        }

        $dompdf->loadHtml($html);

        $dompdf->setPaper('A4','portrait');

        $dompdf->render();

        $dompdf->stream('test.pdf');
    }
}

add_action('wp',function () {
    global $wp_query;
    $myPlugin = new MyPlugin($wp_query);
    $myPlugin->add_button();
});

function me_post_pdf()
{
    if (isset($_POST['me_post_pdf'])) {
        global $wp_query;
        $myPlugin2 = new MyPlugin($wp_query);
        $content = $myPlugin2->get_car_photos($myPlugin2->getPostId(),'car');
        $myPlugin2->process_pdf($content);
    }
}

add_action('init','me_post_pdf'); ```

For some reason this doesn't work. I'm using a library called `dompdf` to generate the pdf. Can anyone please guide me?

Thank you