RSS Feed 生成后，如何设置才能给网站添加 RSS 呢？并且让 Firefox、IE7 或其它 Feed 机器人自动发现？很简单，在网页的 Head 节添加一个特定的 Link 标签即可，如下：
设置 title 为 Feed 标题，href 为 Feed 地址，一切就 OK 了！
例子2
php程序员教程网
https://www.111cn.net/
本站是一个php程序员的工作生活笔记!RSS Tutorial
网站地址/rss
New RSS tutorial on W3SchoolXML Tutorial
网站地址/xml
New XML tutorial on W3School
下面分享一段使用 php 动态生成 RSS 的代码示例：
description);
$descriptionField->syndicateHtml=$this->descriptionHtmlSyndicated;
$descriptionField->truncSize=$this->descriptionTruncSize;
return $descriptionField->output();
}
}
class FeedHtmlField{
var $rawFieldContent;
var $truncSize,$syndicateHtml;
function FeedHtmlField($parFieldContent){
if($parFieldContent){
$this->rawFieldContent=$parFieldContent;
}
}
function output(){
if(!$this->rawFieldContent){
$result="";
} elseif($this->syndicateHtml){
$result="rawFieldContent."]]>";
}else{
if($this->truncSize and is_int($this->truncSize)){
$result=FeedCreator::iTrunc(htmlspecialchars($this->rawFieldContent),$this->truncSize);
}else{
$result=htmlspecialchars($this->rawFieldContent);
}
}
return $result;
}
}
class UniversalFeedCreator extends FeedCreator{
var $_feed;
function _setFormat($format){
switch (strtoupper($format)){
case "2.0":
// fall through
case "RSS2.0":
$this->_feed=new RSSCreator20();
break;
case "0.91":
// fall through
case "RSS0.91":
$this->_feed=new RSSCreator091();
break;
default:
$this->_feed=new RSSCreator091();
break;
}
$vars=get_object_vars($this);
foreach ($vars as $key => $value){
// prevent overwriting of properties "contentType","encoding"; do not copy "_feed" itself
if(!in_array($key, array("_feed","contentType","encoding"))){
$this->_feed->{$key}=$this->{$key};
}
}
}
function createFeed($format="RSS0.91"){
$this->_setFormat($format);
return $this->_feed->createFeed();
}
function saveFeed($format="RSS0.91",$filename="",$displayContents=true){
$this->_setFormat($format);
$this->_feed->saveFeed($filename,$displayContents);
}
function useCached($format="RSS0.91",$filename="",$timeout=3600){
$this->_setFormat($format);
$this->_feed->useCached($filename,$timeout);
}
}
class FeedCreator extends HtmlDescribable{
var $title,$description,$link;
var $syndicationURL,$image,$language,$copyright,$pubDate,$lastBuildDate,$editor,$editorEmail,$webmaster,$category,$docs,$ttl,$rating,$skipHours,$skipDays;
var $xslStyleSheet="";
var $items=Array();
var $contentType="application/xml";
var $encoding="utf-8";
var $additionalElements=Array();
function addItem($item){
$this->items[]=$item;
}
function clearItem2Null(){
$this->items=array();
}
function iTrunc($string,$length){
if(strlen($string)=$length-4){
$string=substr($string,0,$length-4);
$pos=strrpos($string,".");
}
if($pos>=$length*0.4){
return substr($string,0,$pos+1)." ...";
}
$pos=strrpos($string," ");
if($pos>=$length-4){
$string=substr($string,0,$length-4);
$pos=strrpos($string," ");
}
if($pos>=$length*0.4){
return substr($string,0,$pos)." ...";
}
return substr($string,0,$length-4)." ...";
}
function _createGeneratorComment(){
return "n";
}
function _createAdditionalElements($elements,$indentString=""){
$ae="";
if(is_array($elements)){
foreach($elements AS $key => $value){
$ae.= $indentString."$value$key>n";
}
}
return $ae;
}
function _createStylesheetReferences(){
$xml="";
if($this->cssStyleSheet) $xml .= "cssStyleSheet."" type="text/css"?>n";
if($this->xslStyleSheet) $xml .= "xslStyleSheet."" type="text/xsl"?>n";
return $xml;
}
function createFeed(){}
function _generateFilename(){
$fileInfo=pathinfo($_SERVER["PHP_SELF"]);
return substr($fileInfo["basename"],0,-(strlen($fileInfo["extension"])+1)).".xml";
}
function _redirect($filename){
Header("Content-Type: ".$this->contentType."; charset=".$this->encoding."; filename=".basename($filename));
Header("Content-Disposition: inline; filename=".basename($filename));
readfile($filename,"r");
die();
}
function useCached($filename="",$timeout=3600){
$this->_timeout=$timeout;
if($filename==""){
$filename=$this->_generateFilename();
}
if(file_exists($filename) && (time()-filemtime($filename) _redirect($filename);
}
}
function saveFeed($filename="",$displayContents=true){
if($filename==""){
$filename=$this->_generateFilename();
}
$feedFile=fopen($filename,"w+");
if($feedFile){
fputs($feedFile,$this->createFeed());
fclose($feedFile);
if($displayContents){
$this->_redirect($filename);
}
}else{
echo " Error creating feed file, please check write permissions. ";
}
}
}
class FeedDate{
var $unix;
function FeedDate($dateString=""){
if($dateString=="") $dateString=date("r");
if(is_integer($dateString)){
$this->unix=$dateString;
return;
}
if(preg_match("~(?:(?:Mon|Tue|Wed|Thu|Fri|Sat|Sun),\s+)?(\d{1,2})\s+([a-zA-Z]{3})\s+(\d{4})\s+(\d{2}):(\d{2}):(\d{2})\s+(.*)~",$dateString,$matches)){
$months=Array("Jan"=>1,"Feb"=>2,"Mar"=>3,"Apr"=>4,"May"=>5,"Jun"=>6,"Jul"=>7,"Aug"=>8,"Sep"=>9,"Oct"=>10,"Nov"=>11,"Dec"=>12);
$this->unix=mktime($matches[4],$matches[5],$matches[6],$months[$matches[2]],$matches[1],$matches[3]);
if(substr($matches[7],0,1)=='+' OR substr($matches[7],0,1)=='-'){
$tzOffset=(substr($matches[7],0,3) * 60 + substr($matches[7],-2)) * 60;
}else{
if(strlen($matches[7])==1){
$oneHour=3600;
$ord=ord($matches[7]);
if($ord = ord("M") && $matches[7]!="Z"){
$tzOffset=($ord - ord("M")) * $oneHour;
} elseif($matches[7]=="Z"){
$tzOffset=0;
}
}
switch ($matches[7]){
case "UT":
case "GMT": $tzOffset=0;
}
}
$this->unix += $tzOffset;
return;
}
if(preg_match("~(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(.*)~",$dateString,$matches)){
$this->unix=mktime($matches[4],$matches[5],$matches[6],$matches[2],$matches[3],$matches[1]);
if(substr($matches[7],0,1)=='+' OR substr($matches[7],0,1)=='-'){
$tzOffset=(substr($matches[7],0,3) * 60 + substr($matches[7],-2)) * 60;
}else{
if($matches[7]=="Z"){
$tzOffset=0;
}
}
$this->unix += $tzOffset;
return;
}
$this->unix=0;
}
function rfc822(){
$date=gmdate("Y-m-d H:i:s",$this->unix);
if(TIME_ZONE!="") $date .= " ".str_replace(":","",TIME_ZONE);
return $date;
}
function iso8601(){
$date=gmdate("Y-m-d H:i:s",$this->unix);
$date=substr($date,0,22) . ':' . substr($date,-2);
if(TIME_ZONE!="") $date=str_replace("+00:00",TIME_ZONE,$date);
return $date;
}
function unix(){
return $this->unix;
}
}
class RSSCreator10 extends FeedCreator{
function createFeed(){
$feed="encoding.""?>n";
$feed.= $this->_createGeneratorComment();
if($this->cssStyleSheet==""){
$cssStyleSheet="http://www.***w3.org/2000/08/w3c-synd/style.css";
}
$feed.= $this->_createStylesheetReferences();
$feed.= "n";
$feed.= " syndicationURL."">n";
$feed.= " ".htmlspecialchars($this->title)."n";
$feed.= " ".htmlspecialchars($this->description)."n";
$feed.= " ".$this->link."n";
if($this->image!=null){
$feed.= " image->url."" />n";
}
$now=new FeedDate();
$feed.= " ".htmlspecialchars($now->iso8601())."n";
$feed.= " n";
$feed.= " n";
for ($i=0;$iitems);$i++){
$feed.= "
