php生成RSS订阅的方法
本文实例讲述了php生成RSS订阅的方法。分享给大家供大家参考。具体分析如下:
RSS(简易信息聚合,也叫聚合内容)是一种描述和同步网站内容的格式。RSS可以是以下三个解释的其中一个:ReallySimpleSyndication;RDF(ResourceDescriptionFramework)SiteSummary;RichSiteSummary。但其实这三个解释都是指同一种Syndication的技术。RSS目前广泛用于网上新闻频道,blog和wiki。使用RSS订阅能更快地获取信息,网站提供RSS输出,有利于让用户获取网站内容的最新更新。网络用户可以在客户端借助于支持RSS的聚合工具软件,在不打开网站内容页面的情况下阅读支持RSS输出的网站内容。
从技术上来说一个RSS文件就是一段规范的XML数据,该文件一般以rss,xml或者rdf作为后缀,下面是一段rss文件的内容示例:
<?xmlversion="1.0"encoding="utf-8"?> <rssversion="2.0"> <channel> <title>毛票票</title> <link>https://www.nhooo.com/</link> <description>毛票票</description> <item> <title>RSSTutorial</title> <link>网站地址/rss</link> <description>NewRSStutorialonW3School</description> </item> <item> <title>XMLTutorial</title> <link>网站地址/xml</link> <description>NewXMLtutorialonW3School</description> </item> </channel> </rss>
下面分享一段使用php动态生成RSS的代码示例:
<?php /** **php动态生成RSS类 **/ define("TIME_ZONE",""); define("FEEDCREATOR_VERSION","www.nhooo.com");//您的网址 classFeedItemextendsHtmlDescribable{ var$title,$description,$link; var$author,$authorEmail,$image,$category,$comments,$guid,$source,$creator; var$date; var$additionalElements=Array(); } classFeedImageextendsHtmlDescribable{ var$title,$url,$link; var$width,$height,$description; } classHtmlDescribable{ var$descriptionHtmlSyndicated; var$descriptionTruncSize; functiongetDescription(){ $descriptionField=newFeedHtmlField($this->description); $descriptionField->syndicateHtml=$this->descriptionHtmlSyndicated; $descriptionField->truncSize=$this->descriptionTruncSize; return$descriptionField->output(); } } classFeedHtmlField{ var$rawFieldContent; var$truncSize,$syndicateHtml; functionFeedHtmlField($parFieldContent){ if($parFieldContent){ $this->rawFieldContent=$parFieldContent; } } functionoutput(){ if(!$this->rawFieldContent){ $result=""; } elseif($this->syndicateHtml){ $result="<![CDATA[".$this->rawFieldContent."]]>"; }else{ if($this->truncSizeandis_int($this->truncSize)){ $result=FeedCreator::iTrunc(htmlspecialchars($this->rawFieldContent),$this->truncSize); }else{ $result=htmlspecialchars($this->rawFieldContent); } } return$result; } } classUniversalFeedCreatorextendsFeedCreator{ var$_feed; function_setFormat($format){ switch(strtoupper($format)){ case"2.0": //fallthrough case"RSS2.0": $this->_feed=newRSSCreator20(); break; case"0.91": //fallthrough case"RSS0.91": $this->_feed=newRSSCreator091(); break; default: $this->_feed=newRSSCreator091(); break; } $vars=get_object_vars($this); foreach($varsas$key=>$value){ //preventoverwritingofproperties"contentType","encoding";donotcopy"_feed"itself if(!in_array($key,array("_feed","contentType","encoding"))){ $this->_feed->{$key}=$this->{$key}; } } } functioncreateFeed($format="RSS0.91"){ $this->_setFormat($format); return$this->_feed->createFeed(); } functionsaveFeed($format="RSS0.91",$filename="",$displayContents=true){ $this->_setFormat($format); $this->_feed->saveFeed($filename,$displayContents); } functionuseCached($format="RSS0.91",$filename="",$timeout=3600){ $this->_setFormat($format); $this->_feed->useCached($filename,$timeout); } } classFeedCreatorextendsHtmlDescribable{ var$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(); functionaddItem($item){ $this->items[]=$item; } functionclearItem2Null(){ $this->items=array(); } functioniTrunc($string,$length){ if(strlen($string)<=$length){ return$string; } $pos=strrpos($string,"."); if($pos>=$length-4){ $string=substr($string,0,$length-4); $pos=strrpos($string,"."); } if($pos>=$length*0.4){ returnsubstr($string,0,$pos+1)."..."; } $pos=strrpos($string,""); if($pos>=$length-4){ $string=substr($string,0,$length-4); $pos=strrpos($string,""); } if($pos>=$length*0.4){ returnsubstr($string,0,$pos)."..."; } returnsubstr($string,0,$length-4)."..."; } function_createGeneratorComment(){ return"<!--generator=\"".FEEDCREATOR_VERSION."\"-->\n"; } function_createAdditionalElements($elements,$indentString=""){ $ae=""; if(is_array($elements)){ foreach($elementsAS$key=>$value){ $ae.=$indentString."<$key>$value</$key>\n"; } } return$ae; } function_createStylesheetReferences(){ $xml=""; if($this->cssStyleSheet)$xml.="<?xml-stylesheethref=\"".$this->cssStyleSheet."\"type=\"text/css\"?>\n"; if($this->xslStyleSheet)$xml.="<?xml-stylesheethref=\"".$this->xslStyleSheet."\"type=\"text/xsl\"?>\n"; return$xml; } functioncreateFeed(){} function_generateFilename(){ $fileInfo=pathinfo($_SERVER["PHP_SELF"]); returnsubstr($fileInfo["basename"],0,-(strlen($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(); } functionuseCached($filename="",$timeout=3600){ $this->_timeout=$timeout; if($filename==""){ $filename=$this->_generateFilename(); } if(file_exists($filename)&&(time()-filemtime($filename)<$timeout)){ $this->_redirect($filename); } } functionsaveFeed($filename="",$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"<br/><b>Errorcreatingfeedfile,pleasecheckwritepermissions.</b><br/>"; } } } classFeedDate{ var$unix; functionFeedDate($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($matches[7],0,1)=='+'ORsubstr($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")){ $tzOffset=(ord("A")-$ord-1)*$oneHour; }elseif($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)=='+'ORsubstr($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; } functionrfc822(){ $date=gmdate("Y-m-dH:i:s",$this->unix); if(TIME_ZONE!="")$date.="".str_replace(":","",TIME_ZONE); return$date; } functioniso8601(){ $date=gmdate("Y-m-dH:i:s",$this->unix); $date=substr($date,0,22).':'.substr($date,-2); if(TIME_ZONE!="")$date=str_replace("+00:00",TIME_ZONE,$date); return$date; } functionunix(){ return$this->unix; } } classRSSCreator10extendsFeedCreator{ functioncreateFeed(){ $feed="<?xmlversion=\"1.0\"encoding=\"".$this->encoding."\"?>\n"; $feed.=$this->_createGeneratorComment(); if($this->cssStyleSheet==""){ $cssStyleSheet="http://www.w3.org/2000/08/w3c-synd/style.css"; } $feed.=$this->_createStylesheetReferences(); $feed.="<rdf:RDF\n"; $feed.=" xmlns=\"http://purl.org/rss/1.0/\"\n"; $feed.=" xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"\n"; $feed.=" xmlns:slash=\"http://purl.org/rss/1.0/modules/slash/\"\n"; $feed.=" xmlns:dc=\"http://purl.org/dc/elements/1.1/\">\n"; $feed.=" <channelrdf:about=\"".$this->syndicationURL."\">\n"; $feed.=" <title>".htmlspecialchars($this->title)."</title>\n"; $feed.=" <description>".htmlspecialchars($this->description)."</description>\n"; $feed.=" <link>".$this->link."</link>\n"; if($this->image!=null){ $feed.=" <imagerdf:resource=\"".$this->image->url."\"/>\n"; } $now=newFeedDate(); $feed.=" <dc:date>".htmlspecialchars($now->iso8601())."</dc:date>\n"; $feed.=" <items>\n"; $feed.=" <rdf:Seq>\n"; for($i=0;$i<count($this->items);$i++){ $feed.=" <rdf:lirdf:resource=\"".htmlspecialchars($this->items[$i]->link)."\"/>\n"; } $feed.=" </rdf:Seq>\n"; $feed.=" </items>\n"; $feed.=" </channel>\n"; if($this->image!=null){ $feed.=" <imagerdf:about=\"".$this->image->url."\">\n"; $feed.=" <title>".$this->image->title."</title>\n"; $feed.=" <link>".$this->image->link."</link>\n"; $feed.=" <url>".$this->image->url."</url>\n"; $feed.=" </image>\n"; } $feed.=$this->_createAdditionalElements($this->additionalElements," "); for($i=0;$i<count($this->items);$i++){ $feed.=" <itemrdf:about=\"".htmlspecialchars($this->items[$i]->link)."\">\n"; //$feed.=" <dc:type>Posting</dc:type>\n"; $feed.=" <dc:format>text/html</dc:format>\n"; if($this->items[$i]->date!=null){ $itemDate=newFeedDate($this->items[$i]->date); $feed.=" <dc:date>".htmlspecialchars($itemDate->iso8601())."</dc:date>\n"; } if($this->items[$i]->source!=""){ $feed.=" <dc:source>".htmlspecialchars($this->items[$i]->source)."</dc:source>\n"; } if($this->items[$i]->author!=""){ $feed.=" <dc:creator>".htmlspecialchars($this->items[$i]->author)."</dc:creator>\n"; } $feed.=" <title>".htmlspecialchars(strip_tags(strtr($this->items[$i]->title,"\n\r"," ")))."</title>\n"; $feed.=" <link>".htmlspecialchars($this->items[$i]->link)."</link>\n"; $feed.=" <description>".htmlspecialchars($this->items[$i]->description)."</description>\n"; $feed.=$this->_createAdditionalElements($this->items[$i]->additionalElements," "); $feed.=" </item>\n"; } $feed.="</rdf:RDF>\n"; return$feed; } } classRSSCreator091extendsFeedCreator{ var$RSSVersion; functionRSSCreator091(){ $this->_setRSSVersion("0.91"); $this->contentType="application/rss+xml"; } function_setRSSVersion($version){ $this->RSSVersion=$version; } functioncreateFeed(){ $feed="<?xmlversion=\"1.0\"encoding=\"".$this->encoding."\"?>\n"; $feed.=$this->_createGeneratorComment(); $feed.=$this->_createStylesheetReferences(); $feed.="<rssversion=\"".$this->RSSVersion."\">\n"; $feed.=" <channel>\n"; $feed.=" <title>".FeedCreator::iTrunc(htmlspecialchars($this->title),100)."</title>\n"; $this->descriptionTruncSize=500; $feed.=" <description>".$this->getDescription()."</description>\n"; $feed.=" <link>".$this->link."</link>\n"; $now=newFeedDate(); $feed.=" <lastBuildDate>".htmlspecialchars($now->rfc822())."</lastBuildDate>\n"; $feed.=" <generator>".FEEDCREATOR_VERSION."</generator>\n"; if($this->image!=null){ $feed.=" <image>\n"; $feed.=" <url>".$this->image->url."</url>\n"; $feed.=" <title>".FeedCreator::iTrunc(htmlspecialchars($this->image->title),100)."</title>\n"; $feed.=" <link>".$this->image->link."</link>\n"; if($this->image->width!=""){ $feed.=" <width>".$this->image->width."</width>\n"; } if($this->image->height!=""){ $feed.=" <height>".$this->image->height."</height>\n"; } if($this->image->description!=""){ $feed.=" <description>".$this->image->getDescription()."</description>\n"; } $feed.=" </image>\n"; } if($this->language!=""){ $feed.=" <language>".$this->language."</language>\n"; } if($this->copyright!=""){ $feed.=" <copyright>".FeedCreator::iTrunc(htmlspecialchars($this->copyright),100)."</copyright>\n"; } if($this->editor!=""){ $feed.=" <managingEditor>".FeedCreator::iTrunc(htmlspecialchars($this->editor),100)."</managingEditor>\n"; } if($this->webmaster!=""){ $feed.=" <webMaster>".FeedCreator::iTrunc(htmlspecialchars($this->webmaster),100)."</webMaster>\n"; } if($this->pubDate!=""){ $pubDate=newFeedDate($this->pubDate); $feed.=" <pubDate>".htmlspecialchars($pubDate->rfc822())."</pubDate>\n"; } if($this->category!=""){ $feed.=" <category>".htmlspecialchars($this->category)."</category>\n"; } if($this->docs!=""){ $feed.=" <docs>".FeedCreator::iTrunc(htmlspecialchars($this->docs),500)."</docs>\n"; } if($this->ttl!=""){ $feed.=" <ttl>".htmlspecialchars($this->ttl)."</ttl>\n"; } if($this->rating!=""){ $feed.=" <rating>".FeedCreator::iTrunc(htmlspecialchars($this->rating),500)."</rating>\n"; } if($this->skipHours!=""){ $feed.=" <skipHours>".htmlspecialchars($this->skipHours)."</skipHours>\n"; } if($this->skipDays!=""){ $feed.=" <skipDays>".htmlspecialchars($this->skipDays)."</skipDays>\n"; } $feed.=$this->_createAdditionalElements($this->additionalElements," "); for($i=0;$i<count($this->items);$i++){ $feed.=" <item>\n"; $feed.=" <title>".FeedCreator::iTrunc(htmlspecialchars(strip_tags($this->items[$i]->title)),100)."</title>\n"; $feed.=" <link>".htmlspecialchars($this->items[$i]->link)."</link>\n"; $feed.=" <description>".$this->items[$i]->getDescription()."</description>\n"; if($this->items[$i]->author!=""){ $feed.=" <author>".htmlspecialchars($this->items[$i]->author)."</author>\n"; } /* //onhold if($this->items[$i]->source!=""){ $feed.=" <source>".htmlspecialchars($this->items[$i]->source)."</source>\n"; } */ if($this->items[$i]->category!=""){ $feed.=" <category>".htmlspecialchars($this->items[$i]->category)."</category>\n"; } if($this->items[$i]->comments!=""){ $feed.=" <comments>".htmlspecialchars($this->items[$i]->comments)."</comments>\n"; } if($this->items[$i]->date!=""){ $itemDate=newFeedDate($this->items[$i]->date); $feed.=" <pubDate>".htmlspecialchars($itemDate->rfc822())."</pubDate>\n"; } if($this->items[$i]->guid!=""){ $feed.=" <guid>".htmlspecialchars($this->items[$i]->guid)."</guid>\n"; } $feed.=$this->_createAdditionalElements($this->items[$i]->additionalElements," "); $feed.=" </item>\n"; } $feed.=" </channel>\n"; $feed.="</rss>\n"; return$feed; } } classRSSCreator20extendsRSSCreator091{ functionRSSCreator20(){ parent::_setRSSVersion("2.0"); } }
使用示例:
<?php header('Content-Type:text/html;charset=utf-8'); $db=mysql_connect('127.0.0.1','root','123456'); mysql_query("setnamesutf8"); mysql_select_db('dbname',$db); $brs=mysql_query('select*fromarticleorderbyadd_timedesclimit0,10',$db); $rss=newUniversalFeedCreator(); $rss->title="页面标题"; $rss->link="网址http://"; $rss->description="rss标题"; while($rowbrs=mysql_fetch_array($brs)){ $item=newFeedItem(); $item->title=$rowbrs['subject']; $item->link='https://www.nhooo.com/'; $item->description=$rowbrs['description']; $rss->addItem($item); } mysql_close($db); $rss->saveFeed("RSS2.0","rss.xml");
希望本文所述对大家的php程序设计有所帮助。