* @license http://www.gnu.org/licenses/gpl.html GNU General Public
* License (GPL)
* @package PEL
*/
/**
* Class for a user comment.
*
* This class is used to hold user comments, which can come in several
* different character encodings. The Exif standard specifies a
* certain format of the {@link PelTag::USER_COMMENT user comment
* tag}, and this class will make sure that the format is kept.
*
* The most basic use of this class simply stores an ASCII encoded
* string for later retrieval using {@link getValue}:
*
*
* $entry = new PelEntryUserComment('An ASCII string');
* echo $entry->getValue();
*
*
* The string can be encoded with a different encoding, and if so, the
* encoding must be given using the second argument. The Exif
* standard specifies three known encodings: 'ASCII', 'JIS', and
* 'Unicode'. If the user comment is encoded using a character
* encoding different from the tree known encodings, then the empty
* string should be passed as encoding, thereby specifying that the
* encoding is undefined.
*
* @author Martin Geisler
* @package PEL
*/
class PelEntryUserComment extends PelEntryUndefined
{
/**
* The user comment.
*
* @var string
*/
private $comment;
/**
* The encoding.
*
* This should be one of 'ASCII', 'JIS', 'Unicode', or ''.
*
* @var string
*/
private $encoding;
/**
* Make a new entry for holding a user comment.
*
* @param
* string the new user comment.
*
* @param
* string the encoding of the comment. This should be either
* 'ASCII', 'JIS', 'Unicode', or the empty string specifying an
* undefined encoding.
*/
public function __construct($comment = '', $encoding = 'ASCII')
{
parent::__construct(PelTag::USER_COMMENT);
$this->setValue($comment, $encoding);
}
/**
* Set the user comment.
*
* @param
* string the new user comment.
*
* @param
* string the encoding of the comment. This should be either
* 'ASCII', 'JIS', 'Unicode', or the empty string specifying an
* unknown encoding.
*/
public function setValue($comment = '', $encoding = 'ASCII')
{
$this->comment = $comment;
$this->encoding = $encoding;
parent::setValue(str_pad($encoding, 8, chr(0)) . $comment);
}
/**
* Returns the user comment.
*
* The comment is returned with the same character encoding as when
* it was set using {@link setValue} or {@link __construct the
* constructor}.
*
* @return string the user comment.
*/
public function getValue()
{
return $this->comment;
}
/**
* Returns the encoding.
*
* @return string the encoding of the user comment.
*/
public function getEncoding()
{
return $this->encoding;
}
/**
* Returns the user comment.
*
* @return string the user comment.
*/
public function getText($brief = false)
{
return $this->comment;
}
}