rss订阅功能实现原理

听起来很高深.其实就是读取数据,然后输出xml格式的数据.

一种是动态输出rss，另一个是静态输出，原理基本一样，下面的是动态生成rss。

比如我生成就是这样子：

<rss version="2.0" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/">
<channel>
<title>这里是网站名称</title>
<link>网站网址</link>
<description>网站描述</description>
<language>语言</language>
<generator>www.doyouhaobaby.com</generator>
<item>
<title>test</title>
<link>news-139.html</link>
<pubDate>Fri, 24 Jun 2011 01:08:04 +0000</pubDate>
<author></author>
</item>
<item>
<title>ttttttttttttttttttttt3</title>
<link>news-132.html</link>
<pubDate>Wed, 22 Jun 2011 01:44:18 +0000</pubDate>
<author></author>
</item>
</channel>
</rss>

下面是代码!

include ("config.inc.php");
//从数据库中取数据
$log = $DB->getall( "select * from `article` where SortPath like '0,2,%' order by `DateTime` desc limit 0,48 " );

$now = date ( "D,d M Y H:i:s T" );
$blogurl = $_SERVER ["HTTP_HOST"];
$blogurl = "http://" . $blogurl;
header ( 'Content-type: application/xml' );
/*
$d_rss .= "\r\n";
*/
$d_rss .= "\r\n";
$d_rss .= "\r\n";
$d_rss .= "\r\n";
$d_rss .= "http://www.sunhaibing.com\r\n";
$d_rss .= "技术分享\r\n";
$d_rss .= "en-us\r\n";
$d_rss .= "www.doyouhaobaby.com\r\n";

#循环输出rss数据
foreach ( $log as $value ) {
	$d_rss .= "\r\n\r\nnews-" . $value ["Id"] . ".html\r\n" . date ( 'r', $value ['DateTime'] ) . "\r\n" . $value ["Auther"] . "\r\n\r\n";
}

$d_rss .= "\r\n";
#输出到客户端
echo $d_rss;