<?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 = './feed.xml';

    protected $rss = null;

    protected $title = '';

    protected $desc = '';

    protected $link = '';

    public function __construct(){

        $this->title = '物理学';

        $this->desc = '现代物理学';

        $this->link = 'http://mysql/rss.php';

        $this->dom = new DOMDocument('1.0','utf-8');

        $this->dom->load($this->temp);

        $this->rss = $this->dom->getElementsByTagName('rss')->item(0);

    }

    public function feed($arr){

        $this->createChannel();

        $channel = $this->dom->getElementsByTagName('channel')->item(0);

        foreach ($arr as $v){

            $channel->appendChild($this->createItem($v));

        }

        header('content-type:text/xml');

        echo $this->dom->savexml();

    }

    protected function createChannel(){

        $channel = $this->dom->createElement('channel');

        $channel->appendChild($this->createEle('title',$this->title));

        $channel->appendChild($this->createEle('link',$this->link));

        $channel->appendChild($this->createEle('description',$this->desc));

        $this->rss->appendChild($channel);

    }

    protected function createItem($arr){

        $item = $this->dom->createElement('item');

        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(

        'title'=>'牛顿力学',

        'link'=>'1',

        'description'=>'牛顿力学'

    ),

    array(

        'title'=>'相对论',

        'link'=>'1',

        'description'=>'爱因斯坦的相对论'

    )

);

$rss = new Rss;

$rss->feed($arr);

?>