php读取xml文件的三种实现方法

<?php
  $doc = new DOMDocument();
  $doc->load( 'books.xml' );
 
  $books = $doc->getElementsByTagName( "book" );
  foreach( $books as $book )
  {
  $authors = $book->getElementsByTagName( "author" );
  $author = $authors->item(0)->nodeValue;
 
  $publishers = $book->getElementsByTagName( "publisher" );
  $publisher = $publishers->item(0)->nodeValue;
 
  $titles = $book->getElementsByTagName( "title" );
  $title = $titles->item(0)->nodeValue;
 
  echo "$title - $author - $publisher/n";
  }
  ?>

<?php
$parser = xml_parser_create(); //创建一个parser编辑器
xml_set_element_handler($parser, "startElement", "endElement");//设立标签触发时的相应函数 这里分别为startElement和endElenment
xml_set_character_data_handler($parser, "characterData");//设立数据读取时的相应函数
$xml_file="1.xml";//指定所要读取的xml文件,可以是url
$filehandler = fopen($xml_file, "r");//打开文件

while ($data = fread($filehandler, 4096))
{
    xml_parse($parser, $data, feof($filehandler));
}//每次取出4096个字节进行处理

fclose($filehandler);
xml_parser_free($parser);//关闭和释放parser解析器

$name=false;
$position=false;
function startElement($parser_instance, $element_name, $attrs)        //起始标签事件的函数
 {
   global $name,$position; 
   if($element_name=="NAME")
   {
   $name=true;
   $position=false;
   echo "名字:";
  }
  if($element_name=="POSITION")
   {$name=false;
   $position=true;
   echo "职位:";
  }
}

function characterData($parser_instance, $xml_data)                  //读取数据时的函数
{
   global $name,$position;
   if($position)
    echo $xml_data."<br>";
    if($name)
     echo $xml_data."<br>";
}

function endElement($parser_instance, $element_name)                 //结束标签事件的函数
{
 global $name,$position;
$name=false;
$position=false; 
}

?>

<?xml version="1.0"?>
<employees>
<employee>
<name>张三</name>
<position age="45">经理</position>
</employee>
<employees>
<employee>
<name>李四</name>
<position age="45">助理</position>
</employee>
</employees>

// 创建一个新的文档$dom = new DOMDocument('1.0');
// 创建一个根元素<book>并将其添加到文档$book = $dom->appendChild($dom->createElement('book'));
// 创建一个title子元素，并添加到$book中
$title = $book->appendChild($dom->createElement('title'));
// 设置title元素的文本及cover属性
$title->appendChild($dom->createTextNode('PHP Cookbook'));
$title->setAttribute('cover', 'soft');
// 创建并将author元素添加到$book中
$sklar = $book->appendChild($dom->createElement('author'));
//添加文本到author节点$sklar->appendChild($dom->createTextNode('Sklar'));

$trachtenberg = $book->appendChild($dom->createElement('author'));
$trachtenberg->appendChild($dom->createTextNode('Trachtenberg'));

<?xml version="1.0"?>
<address-book>
    <person id="1">
        <!--David Sklar-->
        <firstname>David</firstname>
        <lastname>Sklar</lastname>
        <city>New York</city>
        <state>NY</state>
        <email>sklar@php.net</email>
    </person>

    <person id="2">
        <!--Adam Trachtenberg-->
        <firstname>Adam</firstname>
        <lastname>Trachtenberg</lastname>
        <city>San Francisco</city>
        <state>CA</state>
        <email>amt@php.net</email>
    </person>
</address-book>

$sx = simplexml_load_file('address-book.xml');

foreach ($sx->person as $person) {
    $firstname_text_value = $person->firstname;
    $lastname_text_value = $person->lastname;

    print "$firstname_text_value $lastname_text_valuen";

$dom = new DOMDocument;
$dom->load('address-book.xml');

foreach ($dom->getElementsByTagname('person') as $person) {
    $firstname = $person->getElementsByTagname('firstname');
    $firstname_text_value = $firstname->item(0)->firstChild->nodeValue;

    $lastname = $person->getElementsByTagname('lastname');
    $lastname_text_value = $lastname->item(0)->firstChild->nodeValue;

    print "$firstname_text_value $lastname_text_valuen";
}

$reader = new XMLReader();
$reader->open('card-catalog.xml');

while ($reader->read()) {
    if ($reader->nodeType == XMLREADER::ELEMENT && $reader->localName == 'author') {
        $reader->read();
        print $reader->value . "n";
    }
}

//SimpleXml示例
$emails = $s->xpath('/address-book/preson/email');

$utf_8 = iconv('ISO-8859-1', 'UTF-8', $iso_8859_1);

include 'mysql.php';
$mysql= mysql::getObject();
$mysql->query("SELECT * FROM post");

$xml = new XMLWriter();

$xml->openUri('hello.xml'); //  or 'php://output'

$xml->setIndentString('   ');
$xml->setIndent(true);
// start
$xml->startDocument('1.0', 'UTF-8');

// <rss version="2.0">
$xml->startElement('rss');
   $xml->writeAttribute('version','2.0');
  
 // <channel>
 $xml->startElement('channel');
     // title
     $xml->startElement('title');
          $xml->text('title');
     $xml->endElement();
     // link
     $xml->startElement('link');
          $xml->text('http://foodstory.me/post/');
     $xml->endElement();
     // description
     $xml->startElement('description');
          $xml->text('');
     $xml->endElement();
     // language
     $xml->startElement('language');
          $xml->text('zh-cn');
     $xml->endElement();
     // category
     $xml->startElement('category');
          $xml->text('IT');
     $xml->endElement();
     // copyright
     $xml->startElement('copyright');
          $xml->text('copyright 2011 foodstory.me');
     $xml->endElement();

     // for item
     while( $row = $mysql->fetch() )
     {
      $xml->startElement('item');
         // title
        $xml->startElement('title');
             $xml->text( $row['title']);
        $xml->endElement();
        // link
        $xml->startElement('link');
             $xml->text( 'http://foodstory.me/post/'.$row['id'].'.html');
        $xml->endElement();
        // description
        $xml->startElement('description');
             $xml->text( $row['text'] );
        $xml->endElement();
        // pubDate
        $xml->startElement('pubDate');
             $xml->text( date('D, d M Y H:i:s T', $row['time']) );
        $xml->endElement();
       
        // category tag author need to write .over
      $xml->endElement(); // item
     }
 $xml->endElement(); // channel
$xml->endElement();  // rss

$xml->endDocument();
// $xml->flush();