php如何使用expat方式解析xml文件

<?xml version="1.0" encoding="UTF-8"?>

 
 George
 John
 Reminder
 Don't forget the meeting!
 
 
 George2
 John2
 Reminder2
 Don't forget the meeting!2
 
 
 
 
 

<?php // Initialize the XML parser
$parser = xml_parser_create();
// Function to use at the start of an element
function start($parser, $element_name, $element_attrs)
{
  switch ($element_name) {
    case "NOTE":
      echo "-- Note --
";
      break;
    case "TO":
      echo "To: ";
      break;
    case "FROM":
      echo "From: ";
      break;
    case "HEADING":
      echo "Heading: ";
      break;
    case "BODY":
      echo "Message: ";
  }
}
// Function to use at the end of an element
function stop($parser, $element_name)
{
  echo "
";
}
// Function to use when finding character data
function char($parser, $data)
{
  echo $data;
}
// Specify element handler
xml_set_element_handler($parser, "start", "stop");
// Specify data handler
xml_set_character_data_handler($parser, "char");
// Open XML file
// $fp = fopen("test.xml", "r");
// Read data
// while ($data = fread($fp, 10)) {
// xml_parse($parser, $data, feof($fp)) or die(sprintf("XML Error: %s at line %d", xml_error_string(xml_get_error_code($parser)), xml_get_current_line_number($parser)));
// }
// fclose($fp);
$data = file_get_contents("test.xml");
xml_parse($parser, $data) or die(sprintf("XML Error: %s at line %d", xml_error_string(xml_get_error_code($parser)), xml_get_current_line_number($parser)));
// Free the XML parser
xml_parser_free($parser);
?>