使用PHP DOM-XML创建和解析XML文件
<?php 
  /**
  * Topic:       Create and parse XML files using PHP DOM-XML
  * Source:      http://www.php.net/domxml
  * Reference:   http://www.zugeschaut-und-mitgebaut.de/php/extension.domxml.html
  * Author:      urs@circle.ch, 16-1-2001
  *
  */ 
// 使用PHP DOM-XML创建和解析XML文件

  //创建XML文档对象；以后的处理过程将在此基础上进行
  $doc = new_xmldoc("1.0" ); 

  //创建根节点，并设置一个属性
  $root = $doc->add_root("faq" ); 
  $root->setattr("page", "32" ); 

  //子节点
  $one = $root->new_child("question", ""); 
  //为子节点设置属性
  $one->setattr("number", "1"); 
  //question也创建子节点，并且给它赋值
  $one->new_child("text", "1. Where to get libxml-2.0.0?"); 
  $one->new_child("answer", "You can download the latest
  release of libxml   either as a source archive or
  RPM package from http://www.xmlsoft.org.
  The current version is libxml2-2.2.1." ); 

  $two = $root->new_child("question", "" ); 
  $two->setattr("number", "2"); 
  $two->new_child("text", "2. How to configure PHP4?" ); 
  // 创建一个不直接赋值的节点
  $twoone = $two->new_child("answer", ""); 
  // 然后给它单独赋值
  $twoone->set_content("DIR is the libxml install directory
  (if you just use --with-dom it defaults
  to /usr), I needed to use --with-dom=/usr/local" ); 

  $three = $root->new_child("question", "" ); 
  $three->setattr("number", "7" ); 
  $three->new_child("text", "7. How to use DOM XML function ?" ); 
  $three->new_child("answer", "Read this document source for
  a simple example." ); 

  //输出到Browser
  print("<pre>".htmlspecialchars($doc->dumpmem() )."</pre>" ); 

  // write to file
  //写回到文件
  $fp = fopen("test_dom.xml", "w+" ); 
  fwrite($fp, $doc->dumpmem(), strlen($doc->dumpmem() )); 
  fclose($fp); 

  // ------------------------------------------------------
  //现在使用xpath从XML文档中得到内容
 
  $doc = xmldoc(join("", file("test_dom.xml")) ); 
  $ctx = xpath_new_context($doc ); 

  //所有对象
  $foo = xpath_eval($ctx, "//child::*"); 
  print_r($foo); 
  print("<br/><br/>"); 
  //text node 对象
  $foo = xpath_eval($ctx, "//text"); 
  print_r($foo); 
  print("<br/><br/>"); 
  // 第一个text node对象
  $foo = xpath_eval($ctx, "//text[1]"); 
  print_r($foo); 
  print("<br/><br/>"); 
  // 第二个text node对象
  $foo = xpath_eval($ctx, "//text[2]"); 
  print_r($foo); 
  print("<br/><br/>"); 
  // 第三个answer对象
  $foo = xpath_eval($ctx, "//answer[3]"); 
  print_r($foo); 
  print("<br/><br/>"); 

  //第三个text node的类型，名称和内容
  $foo = xpath_eval($ctx, "//text[3]"); 
  $tmp = $foo->nodeset; 
  print_r($tmp); 
  print("<br/>"); 
  print($tmp[0]->type) . "; "; 
  print($tmp[0]->name) . "; "; 
  print($tmp[0]->content); 

?>