@php $grading = true; // 提取15位paper_id数字部分作为学案编号 $rawPaperId = $paper->paper_id ?? 'unknown'; preg_match('/paper_(\d{15})/', $rawPaperId, $matches); $gradingCode = $matches[1] ?? preg_replace('/[^0-9]/', '', $rawPaperId); @endphp