zentaopms/lib/spout/Reader/CSV/RowIterator.php
2023-05-16 10:47:08 +08:00

261 lines
8.5 KiB
PHP

<?php
namespace Box\Spout\Reader\CSV;
use Box\Spout\Reader\IteratorInterface;
use Box\Spout\Common\Helper\EncodingHelper;
/**
* Class RowIterator
* Iterate over CSV rows.
*
* @package Box\Spout\Reader\CSV
*/
class RowIterator implements IteratorInterface
{
/**
* Value passed to fgetcsv. 0 means "unlimited" (slightly slower but accomodates for very long lines).
*/
const MAX_READ_BYTES_PER_LINE = 0;
/** @var resource Pointer to the CSV file to read */
protected $filePointer;
/** @var int Number of read rows */
protected $numReadRows = 0;
/** @var array|null Buffer used to store the row data, while checking if there are more rows to read */
protected $rowDataBuffer = null;
/** @var bool Indicates whether all rows have been read */
protected $hasReachedEndOfFile = false;
/** @var string Defines the character used to delimit fields (one character only) */
protected $fieldDelimiter;
/** @var string Defines the character used to enclose fields (one character only) */
protected $fieldEnclosure;
/** @var string Encoding of the CSV file to be read */
protected $encoding;
/** @var string End of line delimiter, given by the user as input. */
protected $inputEOLDelimiter;
/** @var bool Whether empty rows should be returned or skipped */
protected $shouldPreserveEmptyRows;
/** @var \Box\Spout\Common\Helper\GlobalFunctionsHelper Helper to work with global functions */
protected $globalFunctionsHelper;
/** @var \Box\Spout\Common\Helper\EncodingHelper Helper to work with different encodings */
protected $encodingHelper;
/** @var string End of line delimiter, encoded using the same encoding as the CSV */
protected $encodedEOLDelimiter;
/**
* @param resource $filePointer Pointer to the CSV file to read
* @param \Box\Spout\Reader\CSV\ReaderOptions $options
* @param \Box\Spout\Common\Helper\GlobalFunctionsHelper $globalFunctionsHelper
*/
public function __construct($filePointer, $options, $globalFunctionsHelper)
{
$this->filePointer = $filePointer;
$this->fieldDelimiter = $options->getFieldDelimiter();
$this->fieldEnclosure = $options->getFieldEnclosure();
$this->encoding = $options->getEncoding();
$this->inputEOLDelimiter = $options->getEndOfLineCharacter();
$this->shouldPreserveEmptyRows = $options->shouldPreserveEmptyRows();
$this->globalFunctionsHelper = $globalFunctionsHelper;
$this->encodingHelper = new EncodingHelper($globalFunctionsHelper);
}
/**
* Rewind the Iterator to the first element
* @link http://php.net/manual/en/iterator.rewind.php
*
* @return void
*/
public function rewind()
{
$this->rewindAndSkipBom();
$this->numReadRows = 0;
$this->rowDataBuffer = null;
$this->next();
}
/**
* This rewinds and skips the BOM if inserted at the beginning of the file
* by moving the file pointer after it, so that it is not read.
*
* @return void
*/
protected function rewindAndSkipBom()
{
$byteOffsetToSkipBom = $this->encodingHelper->getBytesOffsetToSkipBOM($this->filePointer, $this->encoding);
// sets the cursor after the BOM (0 means no BOM, so rewind it)
$this->globalFunctionsHelper->fseek($this->filePointer, $byteOffsetToSkipBom);
}
/**
* Checks if current position is valid
* @link http://php.net/manual/en/iterator.valid.php
*
* @return bool
*/
public function valid()
{
return ($this->filePointer && !$this->hasReachedEndOfFile);
}
/**
* Move forward to next element. Reads data for the next unprocessed row.
* @link http://php.net/manual/en/iterator.next.php
*
* @return void
* @throws \Box\Spout\Common\Exception\EncodingConversionException If unable to convert data to UTF-8
*/
public function next()
{
$this->hasReachedEndOfFile = $this->globalFunctionsHelper->feof($this->filePointer);
if (!$this->hasReachedEndOfFile) {
$this->readDataForNextRow();
}
}
/**
* @return void
* @throws \Box\Spout\Common\Exception\EncodingConversionException If unable to convert data to UTF-8
*/
protected function readDataForNextRow()
{
do {
$rowData = $this->getNextUTF8EncodedRow();
} while ($this->shouldReadNextRow($rowData));
if ($rowData !== false) {
// str_replace will replace NULL values by empty strings
$this->rowDataBuffer = str_replace(null, null, $rowData);
$this->numReadRows++;
} else {
// If we reach this point, it means end of file was reached.
// This happens when the last lines are empty lines.
$this->hasReachedEndOfFile = true;
}
}
/**
* @param array|bool $currentRowData
* @return bool Whether the data for the current row can be returned or if we need to keep reading
*/
protected function shouldReadNextRow($currentRowData)
{
$hasSuccessfullyFetchedRowData = ($currentRowData !== false);
$hasNowReachedEndOfFile = $this->globalFunctionsHelper->feof($this->filePointer);
$isEmptyLine = $this->isEmptyLine($currentRowData);
return (
(!$hasSuccessfullyFetchedRowData && !$hasNowReachedEndOfFile) ||
(!$this->shouldPreserveEmptyRows && $isEmptyLine)
);
}
/**
* Returns the next row, converted if necessary to UTF-8.
* As fgetcsv() does not manage correctly encoding for non UTF-8 data,
* we remove manually whitespace with ltrim or rtrim (depending on the order of the bytes)
*
* @return array|false The row for the current file pointer, encoded in UTF-8 or FALSE if nothing to read
* @throws \Box\Spout\Common\Exception\EncodingConversionException If unable to convert data to UTF-8
*/
protected function getNextUTF8EncodedRow()
{
$encodedRowData = $this->globalFunctionsHelper->fgetcsv($this->filePointer, self::MAX_READ_BYTES_PER_LINE, $this->fieldDelimiter, $this->fieldEnclosure);
if ($encodedRowData === false) {
return false;
}
foreach ($encodedRowData as $cellIndex => $cellValue) {
switch($this->encoding) {
case EncodingHelper::ENCODING_UTF16_LE:
case EncodingHelper::ENCODING_UTF32_LE:
// remove whitespace from the beginning of a string as fgetcsv() add extra whitespace when it try to explode non UTF-8 data
$cellValue = ltrim($cellValue);
break;
case EncodingHelper::ENCODING_UTF16_BE:
case EncodingHelper::ENCODING_UTF32_BE:
// remove whitespace from the end of a string as fgetcsv() add extra whitespace when it try to explode non UTF-8 data
$cellValue = rtrim($cellValue);
break;
}
$encodedRowData[$cellIndex] = $this->encodingHelper->attemptConversionToUTF8($cellValue, $this->encoding);
}
return $encodedRowData;
}
/**
* Returns the end of line delimiter, encoded using the same encoding as the CSV.
* The return value is cached.
*
* @return string
*/
protected function getEncodedEOLDelimiter()
{
if (!isset($this->encodedEOLDelimiter)) {
$this->encodedEOLDelimiter = $this->encodingHelper->attemptConversionFromUTF8($this->inputEOLDelimiter, $this->encoding);
}
return $this->encodedEOLDelimiter;
}
/**
* @param array|bool $lineData Array containing the cells value for the line
* @return bool Whether the given line is empty
*/
protected function isEmptyLine($lineData)
{
return (is_array($lineData) && count($lineData) === 1 && $lineData[0] === null);
}
/**
* Return the current element from the buffer
* @link http://php.net/manual/en/iterator.current.php
*
* @return array|null
*/
public function current()
{
return $this->rowDataBuffer;
}
/**
* Return the key of the current element
* @link http://php.net/manual/en/iterator.key.php
*
* @return int
*/
public function key()
{
return $this->numReadRows;
}
/**
* Cleans up what was created to iterate over the object.
*
* @return void
*/
public function end()
{
// do nothing
}
}