phpspreadsheet 如何设置对角线

$styleArray = [
                'borders' => [
                    'diagonal' => [
                        'borderStyle' => \PhpOffice\PhpSpreadsheet\Style\Border::BORDER_THIN,
                        'color' => ['argb' => 'FFFF0000'],
                    ],
                ],
            ];

下面这两种方式都没有效果，请问我是哪里写错了吗

$worksheet->getCell('J'.$num)->getStyle()->applyFromArray($styleArray);
$worksheet->getStyle('J'.$num)->applyFromArray($styleArray);