HELP!!! [Try to make class for parsing XML]

Hi!!! Please Help me. I look on it code 2 hours and cant see what wrong!

class TPageData
{
     var $FileName;
 var $start_element;
 var $end_element;
 var $data_of_element;
 var $currentElement;

 function makeFileParser()
 {
         /* Creating the xml parser */
         $xml_parser = xml_parser_create();

         xml_set_element_handler($xml_parser, $this->start_element,
$this->end_element);
         xml_set_character_data_handler($xml_parser,
$this->data_of_element);

         xml_parser_set_option ($xml_parser, XML_OPTION_CASE_FOLDING,
FALSE);


         if (!($fp = fopen($this->FileName,"r")))
  {
              die("Cannot open $xmlSource.");
         }
         while (($data = fread($fp,4096)))
  {
              if (!xml_parse($xml_parser, $data, feof($fp)))
   {
                  die (sprintf("XML error at line %d column %d ",
                       xml_get_current_line_number($xml_parser),
                       xml_get_current_column_number($xml_parser)));
              }
         }

  fclose($fp);
         xml_parser_free($xml_parser);
     }


 function startElement($parser, $name, $attr)
     {
  $this->currentElement = $name;
        }

 function endElement($parser, $name)
     {
 }

 function characterData($parser, $data)
 {
  print "!_" . $this->currentElement . "_!";  // AND I SEE "!__!" ON THE
SCREEN. IT MEANS THAT currentElement HAVNT VALUE/ WHY??????
  if ($this->currentElement == 'page_title')
  {
   $this->pageTitle = $data;
  }
 }

 function TPageData($Name)
 {
  $this->FileName = $Name;

  $this->start_element = array($this,"startElement");
  $this->end_element = array($this,"endElement");
  $this->data_of_element = array($this,"characterData");


  $this->makeFileParser();
 }

}