* @license http://www.gnu.org/licenses/gpl.html GNU General Public
* License (GPL)
* @package PEL
*/
/**
* Class used to manipulate strings in the format Windows XP uses.
*
* When examining the file properties of an image in Windows XP one
* can fill in title, comment, author, keyword, and subject fields.
* Filling those fields and pressing OK will result in the data being
* written into the Exif data in the image.
*
* The data is written in a non-standard format and can thus not be
* loaded directly --- this class is needed to translate it into
* normal strings.
*
* It is important that entries from this class are only created with
* the {@link PelTag::XP_TITLE}, {@link PelTag::XP_COMMENT}, {@link
* PelTag::XP_AUTHOR}, {@link PelTag::XP_KEYWORD}, and {@link
* PelTag::XP_SUBJECT} tags. If another tag is used the data will no
* longer be correctly decoded when reloaded with PEL. (The data will
* be loaded as an {@link PelEntryByte} entry, which isn't as useful.)
*
* This class is to be used as in
*
* $title = $ifd->getEntry(PelTag::XP_TITLE);
* print($title->getValue());
* $title->setValue('My favorite cat');
*
* or if no entry is present one can add a new one with
*
* $title = new PelEntryWindowsString(PelTag::XP_TITLE, 'A cute dog.');
* $ifd->addEntry($title);
*
*
* @author Martin Geisler
* @package PEL
*/
class PelEntryWindowsString extends PelEntry
{
/**
* The string hold by this entry.
*
* This is the string that was given to the {@link __construct
* constructor} or later to {@link setValue}, without any extra NULL
* characters or any such nonsense.
*
* @var string
*/
private $str;
/**
* Make a new PelEntry that can hold a Windows XP specific string.
*
* @param int $tag
* the tag which this entry represents. This should be
* one of {@link PelTag::XP_TITLE}, {@link PelTag::XP_COMMENT},
* {@link PelTag::XP_AUTHOR}, {@link PelTag::XP_KEYWORD}, and {@link
* PelTag::XP_SUBJECT} tags. If another tag is used, then this
* entry will be incorrectly reloaded as a {@link PelEntryByte}.
*
* @param string $str
* the string that this entry will represent. It will
* be passed to {@link setValue} and thus has to obey its
* requirements.
*/
public function __construct($tag, $str = '')
{
$this->tag = $tag;
$this->format = PelFormat::BYTE;
$this->setValue($str);
}
/**
* Give the entry a new value.
*
* This will overwrite the previous value. The value can be
* retrieved later with the {@link getValue} method.
*
* @param string $str
* the new value of the entry. This should be use the
* Latin-1 encoding and be given without any extra NULL characters.
*/
public function setValue($str)
{
$l = strlen($str);
$this->components = 2 * ($l + 1);
$this->str = $str;
$this->bytes = '';
for ($i = 0; $i < $l; $i ++) {
$this->bytes .= $str{$i} . chr(0x00);
}
$this->bytes .= chr(0x00) . chr(0x00);
}
/**
* Return the string of the entry.
*
* @return string the string held, without any extra NULL
* characters. The string will be the same as the one given to
* {@link setValue} or to the {@link __construct constructor}.
*/
public function getValue()
{
return $this->str;
}
/**
* Return the string of the entry.
*
* This methods returns the same as {@link getValue}.
*
* @param boolean $brief
* not used.
*
* @return string the string held, without any extra NULL
* characters. The string will be the same as the one given to
* {@link setValue} or to the {@link __construct constructor}.
*/
public function getText($brief = false)
{
return $this->str;
}
}