Vendor/phpspreadsheet/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Reader/Xls.php
private function readPrintGridlines()
    {
        $length = self::getUInt2d($this->data, $this->pos + 2);
        $recordData = $this->readRecordData($this->data, $this->pos + 4, $length);

        // move stream pointer to next record
        $this->pos += 4 + $length;

        if ($this->version == self::XLS_BIFF8 && !$this->readDataOnly) {
            // offset: 0; size: 2; 0 = do not print sheet grid lines; 1 = print sheet gridlines
            $printGridlines = (bool) self::getUInt2d($recordData, 0);
            $this->phpSheet->setPrintGridlines($printGridlines);
        }
    }
private function readPrintGridlines()
    {
        $length = self::getUInt2d($this->data, $this->pos + 2);
        $recordData = $this->readRecordData($this->data, $this->pos + 4, $length);

        // move stream pointer to next record
        $this->pos += 4 + $length;

        if ($this->version == self::XLS_BIFF8 && !$this->readDataOnly) {
            // offset: 0; size: 2; 0 = do not print sheet grid lines; 1 = print sheet gridlines
            $printGridlines = (bool) self::getUInt2d($recordData, 0);
            $this->phpSheet->setPrintGridlines($printGridlines);
        }
    }
Read PRINTGRIDLINES record.