假设您将此创建为plugin 您已经将dompdf目录保存在插件目录中，您可以将其包含在以下内容中。

// wp-content/plugins/yourplugin/yourplugin.php
// Set up paths to include DOMPDF
$plugin_path = plugin_dir_path( __FILE__ );
define( \'YOURPLUGIN_DOMPDF\', $plugin_path . \'dompdf/\' );

// Set up directory to save PDF
$upload_dir = wp_upload_dir();
define( \'YOURPLUGIN_UPLOAD_DIR\', $upload_dir[\'basedir\'] . \'/invoices\');
define( \'YOURPLUGIN_UPLOAD_URL\', $upload_dir[\'baseurl\'] . \'/invoices\');

include( YOURPLUGIN_DOMPDF . \'autoload.inc.php\' );
use Dompdf\\Dompdf;
use Dompdf\\Options;

function yourplugin_order_invoice_pdf(){
  // validate and sanitize your input 
  $options = new Options();
  $options->set(\'isRemoteEnabled\', true);
  $dompdf = new Dompdf($options);

  if ( ! $html = yourplugin_generate_invoice_html( $order_id ) ) {
    return;
  }

  $dompdf->load_html($html);
  $dompdf->render();
  $output = $dompdf->output();
  wp_mkdir_p( YOURPLUGIN_UPLOAD_DIR );
  $file_name = \'order-\'.$order_id.\'.pdf\';
  $file_path = YOURPLUGIN_UPLOAD_DIR . \'/\'. $file_name;
  file_put_contents( $file_path, $output);
  $invoice_url = YOURPLUGIN_UPLOAD_URL . $file_name;
  return $invoice_url;
}

Theyourplugin_order_invoice_pdf 上述功能是所需组件的一个示例。您可能希望将部分拆分为它们自己的特定功能，并处理您的输入。当然，您需要从Plugin API 将此全部附加到。