php製作基於xml的RSS訂閱源功能範例

<?xml version="1.0" encoding="utf-8"?>
<rss version="2.0" xmlns:wfw="http://wellformedweb.org/CommentAPI/"></rss>

<?php 
class Rss{
  protected $dom = null;
  protected $temp = &#39;./feed.xml&#39;;
  protected $rss = null;
  protected $title = &#39;&#39;;
  protected $desc = &#39;&#39;;
  protected $link = &#39;&#39;;
  public function __construct(){
    $this->title = &#39;物理学&#39;;
    $this->desc = &#39;现代物理学&#39;;
    $this->link = &#39;http://mysql/rss.php&#39;;
    $this->dom = new DOMDocument(&#39;1.0&#39;,&#39;utf-8&#39;);
    $this->dom->load($this->temp);
    $this->rss = $this->dom->getElementsByTagName(&#39;rss&#39;)->item(0);
  }
  public function feed($arr){
    $this->createChannel();
    $channel = $this->dom->getElementsByTagName(&#39;channel&#39;)->item(0);
    foreach ($arr as $v){
      $channel->appendChild($this->createItem($v));
    }
    header(&#39;content-type:text/xml&#39;);
    echo $this->dom->savexml();
  }
  protected function createChannel(){
    $channel = $this->dom->createElement(&#39;channel&#39;);
    $channel->appendChild($this->createEle(&#39;title&#39;,$this->title));
    $channel->appendChild($this->createEle(&#39;link&#39;,$this->link));
    $channel->appendChild($this->createEle(&#39;description&#39;,$this->desc));
    $this->rss->appendChild($channel);
  }
  protected function createItem($arr){
    $item = $this->dom->createElement(&#39;item&#39;);
    foreach($arr as $k => $v){
      $item->appendChild($this->createEle($k,$v));
    }
    return $item;
  }
  protected function createEle($name,$value){
    $e=$this->dom->createElement($name);
    $t=$this->dom->createTextNode($value);
    $e->appendChild($t);
    return $e;
  }
}
$arr = array(
  array(
    &#39;title&#39;=>&#39;牛顿力学&#39;,
    &#39;link&#39;=>&#39;1&#39;,
    &#39;description&#39;=>&#39;牛顿力学&#39;
  ),
  array(
    &#39;title&#39;=>&#39;相对论&#39;,
    &#39;link&#39;=>&#39;1&#39;,
    &#39;description&#39;=>&#39;爱因斯坦的相对论&#39;
  )
);
$rss = new Rss;
$rss->feed($arr);
?>