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PHPExcel User Documentation –

Reading Spreadsheet Files

Author: Mark Baker Version: 1.8. Date: 02 March 2014

Contents

• 1. Spreadsheet File Formats..............................................................................................
• 2. Security.........................................................................................................................
• 3. Loading a Spreadsheet File............................................................................................
• 4. Creating a Reader and Loading a Spreadsheet File.......................................................
• 5. Spreadsheet Reader Options.........................................................................................
  • 5.1. Reading Only Data from a Spreadsheet File............................................................
  • 5.2. Reading Only Named WorkSheets from a File..........................................................
  • 5.3. Reading Only Specific Columns and Rows from a File (Read Filters)......................
  • 5.4. Combining Multiple Files into a Single PHPExcel Object.........................................
  • across multiple Worksheets........................................................................................... 5.5. Combining Read Filters with the setSheetIndex() method to split a large CSV file
  • 5.6. Pipe or Tab Separated Value Files..........................................................................
  • 5.7. A Brief Word about the Advanced Value Binder.....................................................
• 6. Error Handling..............................................................................................................
• 7. Helper Methods............................................................................................................

using eXtensible Markup Language (XML) markup, and the file is then compressed using the GNU project's gzip compression library. http://projects.gnome.org/gnumeric/doc/file-format-gnumeric.shtml

CSV

Comma Separated Value (CSV) file format is a common structuring strategy for text format files. In CSV flies, each line in the file represents a row of data and (within each line of the file) the different data fields (or columns) are separated from one another using a comma (“,”). If a data field contains a comma, then it should be enclosed (typically in quotation marks ("). Sometimes tabs “\t” or the pipe symbol (“|”) are used as separators instead of a comma. Because CSV is a text-only format, it doesn't support any data formatting options.

2. Security

XML-based formats such as OfficeOpen XML, Excel2003 XML, OASIS and Gnumeric are susceptible to XML External Entity Processing (XXE) injection attacks (for an explanation of XXE injection see http://websec.io/2012/08/27/Preventing-XEE-in-PHP.html) when reading spreadsheet files. This can lead to:  Disclosure whether a file is existent  Server Side Request Forgery  Command Execution (depending on the installed PHP wrappers) To prevent this, PHPExcel sets libxml_disable_entity_loader to true for the XML-based Readers by default.

4. Creating a Reader and Loading a Spreadsheet File

If you know the file type of the spreadsheet file that you need to load, you can instantiate a new reader object for that file type, then use the reader's load() method to read the file to a PHPExcel object. It is possible to instantiate the reader objects for each of the different supported filetype by name. However, you may get unpredictable results if the file isn't of the right type (e.g. it is a CSV with an extension of .xls), although this type of exception should normally be trapped. $inputFileName = './sampleData/example1.xls'; /** Create a new Excel5 Reader / $objReader = new PHPExcel_Reader_Excel5(); // $objReader = new PHPExcel_Reader_Excel2007(); // $objReader = new PHPExcel_Reader_Excel2003XML(); // $objReader = new PHPExcel_Reader_OOCalc(); // $objReader = new PHPExcel_Reader_SYLK(); // $objReader = new PHPExcel_Reader_Gnumeric(); // $objReader = new PHPExcel_Reader_CSV(); / Load $inputFileName to a PHPExcel Object / $objPHPExcel = $objReader->load($inputFileName); See Examples/Reader/exampleReader02.php for a working example of this code. Alternatively, you can use the IO Factory's createReader() method to instantiate the reader object for you, simply telling it the file type of the reader that you want instantiating. $inputFileType = 'Excel5'; // $inputFileType = 'Excel2007'; // $inputFileType = 'Excel2003XML'; // $inputFileType = 'OOCalc'; // $inputFileType = 'SYLK'; // $inputFileType = 'Gnumeric'; // $inputFileType = 'CSV'; $inputFileName = './sampleData/example1.xls'; / Create a new Reader of the type defined in $inputFileType / $objReader = PHPExcel_IOFactory::createReader($inputFileType); / Load $inputFileName to a PHPExcel Object **/ $objPHPExcel = $objReader->load($inputFileName); See Examples/Reader/exampleReader03.php for a working example of this code. If you're uncertain of the filetype, you can use the IO Factory's identify() method to identify the reader that you need, before using the createReader() method to instantiate the reader object.

$inputFileName = './sampleData/example1.xls'; /** Identify the type of $inputFileName / $inputFileType = PHPExcel_IOFactory::identify($inputFileName); / Create a new Reader of the type that has been identified / $objReader = PHPExcel_IOFactory::createReader($inputFileType); / Load $inputFileName to a PHPExcel Object **/ $objPHPExcel = $objReader->load($inputFileName); See Examples/Reader/exampleReader04.php for a working example of this code.

5.2. Reading Only Named WorkSheets from a File If your workbook contains a number of worksheets, but you are only interested in reading some of those, then you can use the setLoadSheetsOnly() method to identify those sheets you are interested in reading. To read a single sheet, you can pass that sheet name as a parameter to the setLoadSheetsOnly() method. $inputFileType = 'Excel5'; $inputFileName = './sampleData/example1.xls'; $sheetname = 'Data Sheet #2'; /** Create a new Reader of the type defined in $inputFileType / $objReader = PHPExcel_IOFactory::createReader($inputFileType); / Advise the Reader of which WorkSheets we want to load / $objReader->setLoadSheetsOnly($sheetname); / Load $inputFileName to a PHPExcel Object / $objPHPExcel = $objReader->load($inputFileName); See Examples/Reader/exampleReader07.php for a working example of this code. If you want to read more than just a single sheet, you can pass a list of sheet names as an array parameter to the setLoadSheetsOnly() method. $inputFileType = 'Excel5'; $inputFileName = './sampleData/example1.xls'; $sheetnames = array('Data Sheet #1','Data Sheet #3'); / Create a new Reader of the type defined in $inputFileType / $objReader = PHPExcel_IOFactory::createReader($inputFileType); / Advise the Reader of which WorkSheets we want to load / $objReader->setLoadSheetsOnly($sheetnames); / Load $inputFileName to a PHPExcel Object / $objPHPExcel = $objReader->load($inputFileName); See Examples/Reader/exampleReader08.php for a working example of this code. To reset this option to the default, you can call the setLoadAllSheets() method. $inputFileType = 'Excel5'; $inputFileName = './sampleData/example1.xls'; / Create a new Reader of the type defined in $inputFileType / $objReader = PHPExcel_IOFactory::createReader($inputFileType); / Advise the Reader to load all Worksheets / $objReader->setLoadAllSheets(); / Load $inputFileName to a PHPExcel Object **/ $objPHPExcel = $objReader->load($inputFileName); See Examples/Reader/exampleReader06.php for a working example of this code. Reading Only Named WorkSheets from a File applies to Readers: Excel2007 YES Excel5 YES Excel2003XML YES OOCalc YES SYLK NO Gnumeric YES

CSV NO

/** Define a Read Filter class implementing PHPExcel_Reader_IReadFilter * / class MyReadFilter implements PHPExcel_Reader_IReadFilter { private $_startRow = 0 ; private $_endRow = 0 ; private $_columns = array(); /** Get the list of rows and columns to read / public function __construct($startRow, $endRow, $columns) { $this->_startRow = $startRow; $this->_endRow = $endRow; $this->_columns = $columns; } public function readCell($column, $row, $worksheetName = '') { // Only read the rows and columns that were configured if ($row >= $this->_startRow && $row <= $this->_endRow) { if (in_array($column,$this->_columns)) { return true; } } return false; } } /* Create an Instance of our Read Filter, passing in the cell range **/ $filterSubset = new MyReadFilter( 9 , 15 ,range('G','K')); See Examples/Reader/exampleReader10.php for a working example of this code. This can be particularly useful for conserving memory, by allowing you to read and process a large workbook in “chunks”: an example of this usage might be when transferring data from an Excel worksheet to a database.

$inputFileType = 'Excel5'; $inputFileName = './sampleData/example2.xls'; /** Define a Read Filter class implementing PHPExcel_Reader_IReadFilter * / class chunkReadFilter implements PHPExcel_Reader_IReadFilter { private $_startRow = 0 ; private $_endRow = 0 ; /** Set the list of rows that we want to read / public function setRows($startRow, $chunkSize) { $this->_startRow = $startRow; $this->_endRow = $startRow + $chunkSize; } public function readCell($column, $row, $worksheetName = '') { // Only read the heading row, and the configured rows if (($row == 1 ) || ($row >= $this->_startRow && $row < $this->_endRow)) { return true; } return false; } } /* Create a new Reader of the type defined in $inputFileType / $objReader = PHPExcel_IOFactory::createReader($inputFileType); / Define how many rows we want to read for each "chunk" / $chunkSize = 2048 ; / Create a new Instance of our Read Filter / $chunkFilter = new chunkReadFilter(); / Tell the Reader that we want to use the Read Filter / $objReader->setReadFilter($chunkFilter); / Loop to read our worksheet in "chunk size" blocks / for ($startRow = 2 ; $startRow <= 65536 ; $startRow += $chunkSize) { / Tell the Read Filter which rows we want this iteration / $chunkFilter->setRows($startRow,$chunkSize); / Load only the rows that match our filter **/ $objPHPExcel = $objReader->load($inputFileName); // Do some processing here } See Examples/Reader/exampleReader12.php for a working example of this code. Using Read Filters applies to: Excel2007 YES Excel5 YES Excel2003XML YES OOCalc YES SYLK NO Gnumeric YES CSV YES

5.5. Combining Read Filters with the setSheetIndex() method to split a large CSV file across multiple Worksheets An Excel5 BIFF .xls file is limited to 65536 rows in a worksheet, while the Excel Microsoft Office Open XML SpreadsheetML .xlsx file is limited to 1,048,576 rows in a worksheet; but a CSV file is not limited other than by available disk space. This means that we wouldn’t ordinarily be able to read all the rows from a very large CSV file that exceeded those limits, and save it as an Excel5 or Excel2007 file. However, by using Read Filters to read the CSV file in “chunks” (using the chunkReadFilter Class that we defined in section above), and the setSheetIndex() method of the $objReader, we can split the CSV file across several individual worksheets. $inputFileType = 'CSV'; $inputFileName = './sampleData/example2.csv'; echo 'Loading file ',pathinfo($inputFileName,PATHINFO_BASENAME),' using IOF actory with a defined reader type of ',$inputFileType,'
'; /** Create a new Reader of the type defined in $inputFileType / $objReader = PHPExcel_IOFactory::createReader($inputFileType); / Define how many rows we want to read for each "chunk" / $chunkSize = 65530 ; / Create a new Instance of our Read Filter / $chunkFilter = new chunkReadFilter(); / Tell the Reader that we want to use the Read Filter / / and that we want to store it in contiguous rows/columns / $objReader->setReadFilter($chunkFilter) ->setContiguous(true); / Instantiate a new PHPExcel object manually / $objPHPExcel = new PHPExcel(); / Set a sheet index / $sheet = 0 ; / Loop to read our worksheet in "chunk size" blocks / / $startRow is set to 2 initially because we always read the headings in row #1 / for ($startRow = 2 ; $startRow <= 1000000 ; $startRow += $chunkSize) { / Tell the Read Filter which rows we want to read this loop / $chunkFilter->setRows($startRow,$chunkSize); / Increment the worksheet index pointer for the Reader / $objReader->setSheetIndex($sheet); / Load only the rows that match our filter into a new worksheet / $objReader->loadIntoExisting($inputFileName,$objPHPExcel); / Set the worksheet title for the sheet that we've justloaded) / / and increment the sheet index as well **/ $objPHPExcel->getActiveSheet()->setTitle('Country Data #'.(++$sheet)); } See Examples/Reader/exampleReader14.php for a working example of this code. This code will read 65,530 rows at a time from the CSV file that we’re loading, and store each “chunk” in a new worksheet.

The setContiguous() method for the Reader is important here. It is applicable only when working with a Read Filter, and identifies whether or not the cells should be stored by their position within the CSV file, or their position relative to the filter. For example, if the filter returned true for cells in the range B2:C3, then with setContiguous set to false (the default) these would be loaded as B2:C3 in the PHPExcel object; but with setContiguous set to true, they would be loaded as A1:B2. Splitting a single loaded file across multiple worksheets applies to: Excel2007 NO Excel5 NO Excel2003XML NO OOCalc NO SYLK NO Gnumeric NO CSV YES

5.7. A Brief Word about the Advanced Value Binder When loading data from a file that contains no formatting information, such as a CSV file, then data is read either as strings or numbers (float or integer). This means that PHPExcel does not automatically recognise dates/times (such as “16-Apr-2009” or “13:30”), booleans (“TRUE” or “FALSE”), percentages (“75%”), hyperlinks (“http://www.phpexcel.net”), etc as anything other than simple strings. However, you can apply additional processing that is executed against these values during the load process within a Value Binder. A Value Binder is a class that implement the PHPExcel_Cell_IValueBinder interface. It must contain a bindValue() method that accepts a PHPExcel_Cell and a value as arguments, and return a boolean true or false that indicates whether the workbook cell has been populated with the value or not. The Advanced Value Binder implements such a class: amongst other tests, it identifies a string comprising “TRUE” or “FALSE” (based on locale settings) and sets it to a boolean; or a number in scientific format (e.g. “1.234e-5”) and converts it to a float; or dates and times, converting them to their Excel timestamp value – before storing the value in the cell object. It also sets formatting for strings that are identified as dates, times or percentages. It could easily be extended to provide additional handling (including text or cell formatting) when it encountered a hyperlink, or HTML markup within a CSV file. So using a Value Binder allows a great deal more flexibility in the loader logic when reading unformatted text files. /** Tell PHPExcel that we want to use the Advanced Value Binder **/ PHPExcel_Cell::setValueBinder( new PHPExcel_Cell_AdvancedValueBinder() ); $inputFileType = 'CSV'; $inputFileName = './sampleData/example1.tsv'; $objReader = PHPExcel_IOFactory::createReader($inputFileType); $objReader->setDelimiter("\t"); $objPHPExcel = $objReader->load($inputFileName); See Examples/Reader/exampleReader15.php for a working example of this code. Loading using a Value Binder applies to: Excel2007 NO Excel5 NO Excel2003XML NO OOCalc NO SYLK NO Gnumeric NO CSV YES

6. Error Handling

Of course, you should always apply some error handling to your scripts as well. PHPExcel throws exceptions, so you can wrap all your code that accesses the library methods within Try/Catch blocks to trap for any problems that are encountered, and deal with them in an appropriate manner. The PHPExcel Readers throw a PHPExcel_Reader_Exception. $inputFileName = './sampleData/example-1.xls'; try { /** Load $inputFileName to a PHPExcel Object **/ $objPHPExcel = PHPExcel_IOFactory::load($inputFileName); } catch(PHPExcel_Reader_Exception $e) { die('Error loading file: '.$e->getMessage()); } See Examples/Reader/exampleReader16.php for a working example of this code.