Vendor/phpspreadsheet/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Writer/Csv.php
public function save($pFilename)
    {
        // Fetch sheet
        $sheet = $this->spreadsheet->getSheet($this->sheetIndex);

        $saveDebugLog = Calculation::getInstance($this->spreadsheet)->getDebugLog()->getWriteDebugLog();
        Calculation::getInstance($this->spreadsheet)->getDebugLog()->setWriteDebugLog(false);
        $saveArrayReturnType = Calculation::getArrayReturnType();
        Calculation::setArrayReturnType(Calculation::RETURN_ARRAY_AS_VALUE);

        // Open file
        $fileHandle = fopen($pFilename, 'wb+');
        if ($fileHandle === false) {
            throw new Exception("Could not open file $pFilename for writing.");
        }

        if ($this->excelCompatibility) {
            $this->setUseBOM(true); //  Enforce UTF-8 BOM Header
            $this->setIncludeSeparatorLine(true); //  Set separator line
            $this->setEnclosure('"'); //  Set enclosure to "
            $this->setDelimiter(';'); //  Set delimiter to a semi-colon
            $this->setLineEnding("\r\n");
        }
        if ($this->useBOM) {
            // Write the UTF-8 BOM code if required
            fwrite($fileHandle, "\xEF\xBB\xBF");
        }
        if ($this->includeSeparatorLine) {
            // Write the separator line if required
            fwrite($fileHandle, 'sep=' . $this->getDelimiter() . $this->lineEnding);
        }

        //    Identify the range that we need to extract from the worksheet
        $maxCol = $sheet->getHighestDataColumn();
        $maxRow = $sheet->getHighestDataRow();

        // Write rows to file
        for ($row = 1; $row <= $maxRow; ++$row) {
            // Convert the row to an array...
            $cellsArray = $sheet->rangeToArray('A' . $row . ':' . $maxCol . $row, '', $this->preCalculateFormulas);
            // ... and write to the file
            $this->writeLine($fileHandle, $cellsArray[0]);
        }

        // Close file
        fclose($fileHandle);

        Calculation::setArrayReturnType($saveArrayReturnType);
        Calculation::getInstance($this->spreadsheet)->getDebugLog()->setWriteDebugLog($saveDebugLog);
    }
public function save($pFilename)
    {
        // Fetch sheet
        $sheet = $this->spreadsheet->getSheet($this->sheetIndex);

        $saveDebugLog = Calculation::getInstance($this->spreadsheet)->getDebugLog()->getWriteDebugLog();
        Calculation::getInstance($this->spreadsheet)->getDebugLog()->setWriteDebugLog(false);
        $saveArrayReturnType = Calculation::getArrayReturnType();
        Calculation::setArrayReturnType(Calculation::RETURN_ARRAY_AS_VALUE);

        // Open file
        $fileHandle = fopen($pFilename, 'wb+');
        if ($fileHandle === false) {
            throw new Exception("Could not open file $pFilename for writing.");
        }

        if ($this->excelCompatibility) {
            $this->setUseBOM(true); //  Enforce UTF-8 BOM Header
            $this->setIncludeSeparatorLine(true); //  Set separator line
            $this->setEnclosure('"'); //  Set enclosure to "
            $this->setDelimiter(';'); //  Set delimiter to a semi-colon
            $this->setLineEnding("\r\n");
        }
        if ($this->useBOM) {
            // Write the UTF-8 BOM code if required
            fwrite($fileHandle, "\xEF\xBB\xBF");
        }
        if ($this->includeSeparatorLine) {
            // Write the separator line if required
            fwrite($fileHandle, 'sep=' . $this->getDelimiter() . $this->lineEnding);
        }

        //    Identify the range that we need to extract from the worksheet
        $maxCol = $sheet->getHighestDataColumn();
        $maxRow = $sheet->getHighestDataRow();

        // Write rows to file
        for ($row = 1; $row <= $maxRow; ++$row) {
            // Convert the row to an array...
            $cellsArray = $sheet->rangeToArray('A' . $row . ':' . $maxCol . $row, '', $this->preCalculateFormulas);
            // ... and write to the file
            $this->writeLine($fileHandle, $cellsArray[0]);
        }

        // Close file
        fclose($fileHandle);

        Calculation::setArrayReturnType($saveArrayReturnType);
        Calculation::getInstance($this->spreadsheet)->getDebugLog()->setWriteDebugLog($saveDebugLog);
    }
Save PhpSpreadsheet to file.

@param string $pFilename

@throws Exception