一个生成RSS2.0的php类

<?php
/*****************************************
*           rss2.0 generator
*          create by magicboy(darasion)
*          copyright ? 神奇男孩
******************************************/

/*————————————————

使用方法：
将下面的数组，带入相应的函数。

1、频道主体
$channel = array(
 title => '频道名称(必备)',
 link => '频道的url(必备)',
 description => '频道的描述(必备)',
 language => '频道文章所用语言(可选)',
 webmaster => '负责频道技术事务的网站管理员email(可选)',
 managingeditor => '责任编辑的email(可选)',
 pubdate => '频道内容发布日期，格式遵循rfc822格式（年份可为2位或4位）(可选)',
 lastbuilddate => '频道内容最后的修改日期(sat, 07 sep 2002 09:42:31 gmt)(可选)',
 skipdays => '提示新闻聚合器，那些天它可以跳过。(可选)',
 copyright => '频道内容的版权说明(可选)',
 ttl => '有效期，用以指明该频道可被缓存的最长时间(可选)',
);

2、频道图片
$image = array(
 url => '图片的链接(必备)',
 title => '图片的标题，用于http的alt属性(必备)',
 link => '网站的url(实际中常以频道的url代替)(必备)',
 width => '图片的宽度(象素为单位)最大144,默认88(可选)',
 height => '图片的高度(象素为单位)最大400，默认31(可选)',
 description => '用于link的title属性(可选)'
   );

3、频道项
$item = array(
 title => '项(item)的标题(必备)',
 description => '项的大纲(必备)',
 link => '项的url(必备)',
 comments => '该项的评论(comments)页的url(可选)',
 guid => '1项的唯一标志符串(可选)',
 author => '该项作者的email(可选)',
 enclosure => '描述该附带的媒体对象(可选)',
 category => '包含该项的一个或几个分类(catogory)(可选)',
 pubdate => '项的发布时间(可选)',
 source_url => '该项来自的rss道(可选)',
 source_name => '该项来自的rss道(可选)'
);
————————————————*/

class rss2
{
 var $channel_pre="";
 var $str_image="";
 var $str_item="";
 var $channel_end="";
 /*构造函数*/
 function rss2($channel,$encoding="gb2312")
  {
   $this->channel($channel,$encoding);
  }
 /*生成频道主体*/
 function channel($channel,$encoding="gb2312")
  {
  $this->channel_pre.="<?xml version=/"1.0/" encoding=/"$encoding/"?>/n";
  $this->channel_pre.= "<rss version=/"2.0/">/n";

  $this->channel_pre.= " <channel>/n";

  $this->channel_pre.= "  <title>".$channel['title']."</title>/n";//频道名称(必备)
  $this->channel_pre.= "  <link>".$channel['link']."</link>/n";//频道的url(必备)
  $this->channel_pre.= "  <description>".$channel['description']."</description>/n";//频道的描述(必备)
  $this->channel_pre.= "  <generator>magicboy rss generator v1.0</generator>/n";//创建此文档的程序(可选)

  if(isset($channel['language']))$this->channel_pre.= "  <language>".$channel['language']."</language>/n";//频道文章所用语言(可选)
  if(isset($channel['webmaster']))$this->channel_pre.= "  <webmaster>".$channel['webmaster']."</webmaster>/n";//负责频道技术事务的网站管理员email(可选)
  if(isset($channel['managingeditor']))$this->channel_pre.= "  <managingeditor>".$channel['managingeditor']."</managingeditor>/n";//责任编辑的email(可选)
  if(isset($channel['pubdate']))$this->channel_pre.= "  <pubdate>".$channel['pubdate']."</pubdate>/n";//频道内容发布日期，格式遵循rfc822格式（年份可为2位或4位）(可选)
  if(isset($channel['lastbuilddate']))$this->channel_pre.= "  <lastbuilddate>".$channel['lastbuilddate']."</lastbuilddate>/n";//频道内容最后的修改日期(sat, 07 sep 2002 09:42:31 gmt)(可选)
  if(isset($channel['skipdays']))$this->channel_pre.= "  <skipdays>".$channel['skipdays']."</skipdays>/n";//提示新闻聚合器，那些天它可以跳过。(可选)
  if(isset($channel['copyright']))$this->channel_pre.= "  <copyright>".$channel['copyright']."</copyright>/n";//频道内容的版权说明(可选)
  if(isset($channel['ttl']))$this->channel_pre.= "  <ttl>".$channel['ttl']."</ttl>/n";//有效期，用以指明该频道可被缓存的最长时间(可选)

  $this->channel_end.= " </channel>/n";
  $this->channel_end.= "</rss>/n";
 }
 /*生成频道图片*/
 function image($image)
 {
  if(isset($this->str_image))unset($this->str_image);
  $this->str_image.= "  <image>/n";
  if(isset($image['url']))$this->str_image.= "   <url>".$image['url']."</url>/n";//图片的url(必备)
  if(isset($image['title']))$this->str_image.= "   <title>".$image['title']."</title>/n";//图片的标题，用于http的alt属性(必备)
  if(isset($image['link']))$this->str_image.= "   <link>".$image['link']."</link>/n";//网站的url(实际中常以频道的url代替)(必备)
  if(isset($image['width']))$this->str_image.= "   <width>".$image['width']."</width>/n";//图片的宽度(象素为单位)最大144,默认88(可选)
  if(isset($image['height']))$this->str_image.= "   <height>".$image['height']."</height>/n";//图片的高度(象素为单位)最大400，默认31(可选)
  if(isset($image['description']))$this->str_image.= "   <description>".$image['description']."</description>/n";//用于link的title属性(可选)
  $this->str_image.= "  </image>/n";
 }
 /*频道项*/
 function item($item)
 {
  $this->str_item.="  <item>/n";
  $this->str_item.="   <title>".$item['title']."</title>/n";//项(item)的标题(必备)
  $this->str_item.="   <description>".$item['description']."</description>/n";//项的大纲(必备)
  $this->str_item.="   <link>".$item['link']."</link>/n";//项的url(必备)

  if(isset($item['comments']))$this->str_item.="   <comments>".$item['comments']."</comments>/n";//该项的评论(comments)页的url(可选)
  if(isset($item['guid']))$this->str_item.="   <guid>".$item['guid']."</guid>/n";//1项的唯一标志符串(可选)
  if(isset($item['author']))$this->str_item.="   <author>".$item['author']."</author>/n";//该项作者的email(可选)
  if(isset($item['enclosure']))$this->str_item.="   <enclosure>".$item['enclosure']."</enclosure>/n";//描述该附带的媒体对象(可选)
  if(isset($item['category']))$this->str_item.="   <category>".$item['category']."</category>/n";//包含该项的一个或几个分类(catogory)(可选)
  if(isset($item['pubdate']))$this->str_item.="   <pubdate>".$item['pubdate']."</pubdate>/n";//项的发布时间(可选)
  if(isset($item['source_url']))$this->str_item.="   <source url=/"".$item['source_url']."/">".$item['source_name']."</source>/n";//该项来自的rss道(可选)
  $this->str_item.="  </item>/n";
 }
 /*输出xml*/
 function generate()
 {
  if(isset($this->channel_pre)&&isset($this->channel_end)&&isset($this->str_item))
  {
   header("content-type:text/xml");
   echo $this->channel_pre;
   echo $this->str_image;
   echo $this->str_item;
   echo $this->channel_end;
  }
 }
 /*擦除频道*/
 function erase_channel()
 {
  unset($this->channel_pre);
  unset($this->channel_end);
 }
 /*擦除频道图片*/
 function erase_image()
 {
  unset($this->str_image);
 }
 /*擦除项目*/
 function erase_item()
 {
  unset($this->str_item);
 }
 /*擦除所有*/
 function erase()
 {
  $this->erase_channel();
  $this->erase_image();
  $this->erase_item();
 }
}
?>