search
Homephp教程php手册php生成RSS订阅的方法,phprss订阅

php生成RSS订阅的方法,phprss订阅

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: Really Simple Syndication;RDF (Resource Description Framework) Site Summary; Rich Site Summary。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:

复制代码 代码如下:




帮客之家
http://www.bkjia.com/
帮客之家

RSS Tutorial
网站地址/rss
New RSS tutorial on W3School


XML 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:

复制代码 代码如下:

/**
** php 动态生成 RSS 类
**/
define("TIME_ZONE","");
define("FEEDCREATOR_VERSION","www.jb51.net");//您的网址
class FeedItem extends HtmlDescribable{
    var $title,$description,$link;
    var $author,$authorEmail,$image,$category,$comments,$guid,$source,$creator;
    var $date;
    var $additionalElements=Array();
}
 
class FeedImage extends HtmlDescribable{
    var $title,$url,$link;
    var $width,$height,$description;
}
 
class HtmlDescribable{
    var $descriptionHtmlSyndicated;
    var $descriptionTruncSize;
 
    function getDescription(){
        $descriptionField=new FeedHtmlField($this->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)             return $string;
        }
 
        $pos=strrpos($string,".");
        if($pos>=$length-4){
            $string=substr($string,0,$length-4);
            $pos=strrpos($string,".");
        }
        if($pos>=$length*0.4){
            return substr($string,0,$pos+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)             $this->_redirect($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                         $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)=='+' 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.= "         $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.= "    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.= "               

  • items[$i]->link)."\"/>\n";
            }
            $feed.= "           
  • \n";
            $feed.= "        \n";
            $feed.= "    \n";
            if($this->image!=null){
                $feed.= "    image->url."\">\n";
                $feed.= "        ".$this->image->title."\n";
                $feed.= "        ".$this->image->link."\n";
                $feed.= "        ".$this->image->url."\n";
                $feed.= "    \n";
            }
            $feed.= $this->_createAdditionalElements($this->additionalElements,"    ");
     
            for ($i=0;$iitems);$i++){
                $feed.= "    items[$i]->link)."\">\n";
                //$feed.= "        Posting\n";
                $feed.= "        text/html\n";
                if($this->items[$i]->date!=null){
                    $itemDate=new FeedDate($this->items[$i]->date);
                    $feed.= "        ".htmlspecialchars($itemDate->iso8601())."\n";
                }
                if($this->items[$i]->source!=""){
                    $feed.= "        ".htmlspecialchars($this->items[$i]->source)."\n";
                }
                if($this->items[$i]->author!=""){
                    $feed.= "        ".htmlspecialchars($this->items[$i]->author)."\n";
                }
                $feed.= "        ".htmlspecialchars(strip_tags(strtr($this->items[$i]->title,"\n\r","  ")))."\n";
                $feed.= "        ".htmlspecialchars($this->items[$i]->link)."\n";
                $feed.= "        ".htmlspecialchars($this->items[$i]->description)."\n";
                $feed.= $this->_createAdditionalElements($this->items[$i]->additionalElements,"        ");
                $feed.= "   
    \n";
            }
            $feed.= "\n";
            return $feed;
        }
    }
     
    class RSSCreator091 extends FeedCreator{
        var $RSSVersion;
     
        function RSSCreator091(){
            $this->_setRSSVersion("0.91");
            $this->contentType="application/rss+xml";
        }
     
        function _setRSSVersion($version){
            $this->RSSVersion=$version;
        }
     
        function createFeed(){
            $feed="encoding."\"?>\n";
            $feed.= $this->_createGeneratorComment();
            $feed.= $this->_createStylesheetReferences();
            $feed.= "RSSVersion."\">\n";
            $feed.= "    \n";
            $feed.= "        ".FeedCreator::iTrunc(htmlspecialchars($this->title),100)."\n";
            $this->descriptionTruncSize=500;
            $feed.= "        ".$this->getDescription()."\n";
            $feed.= "        ".$this->link."\n";
            $now=new FeedDate();
            $feed.= "        ".htmlspecialchars($now->rfc822())."\n";
            $feed.= "        ".FEEDCREATOR_VERSION."\n";
     
            if($this->image!=null){
                $feed.= "        \n";
                $feed.= "            ".$this->image->url."\n";
                $feed.= "            ".FeedCreator::iTrunc(htmlspecialchars($this->image->title),100)."\n";
                $feed.= "            ".$this->image->link."\n";
                if($this->image->width!=""){
                    $feed.= "            ".$this->image->width."\n";
                }
                if($this->image->height!=""){
                    $feed.= "            ".$this->image->height."\n";
                }
                if($this->image->description!=""){
                    $feed.= "            ".$this->image->getDescription()."\n";
                }
                $feed.= "        \n";
            }
            if($this->language!=""){
                $feed.= "        ".$this->language."\n";
            }
            if($this->copyright!=""){
                $feed.= "        ".FeedCreator::iTrunc(htmlspecialchars($this->copyright),100)."\n";
            }
            if($this->editor!=""){
                $feed.= "        ".FeedCreator::iTrunc(htmlspecialchars($this->editor),100)."\n";
            }
            if($this->webmaster!=""){
                $feed.= "        ".FeedCreator::iTrunc(htmlspecialchars($this->webmaster),100)."\n";
            }
            if($this->pubDate!=""){
                $pubDate=new FeedDate($this->pubDate);
                $feed.= "        ".htmlspecialchars($pubDate->rfc822())."\n";
            }
            if($this->category!=""){
                $feed.= "        ".htmlspecialchars($this->category)."\n";
            }
            if($this->docs!=""){
                $feed.= "        ".FeedCreator::iTrunc(htmlspecialchars($this->docs),500)."\n";
            }
            if($this->ttl!=""){
                $feed.= "        ".htmlspecialchars($this->ttl)."\n";
            }
            if($this->rating!=""){
                $feed.= "        ".FeedCreator::iTrunc(htmlspecialchars($this->rating),500)."\n";
            }
            if($this->skipHours!=""){
                $feed.= "        ".htmlspecialchars($this->skipHours)."\n";
            }
            if($this->skipDays!=""){
                $feed.= "        ".htmlspecialchars($this->skipDays)."\n";
            }
            $feed.= $this->_createAdditionalElements($this->additionalElements,"    ");
     
            for ($i=0;$iitems);$i++){
                $feed.= "        \n";
                $feed.= "            ".FeedCreator::iTrunc(htmlspecialchars(strip_tags($this->items[$i]->title)),100)."\n";
                $feed.= "            ".htmlspecialchars($this->items[$i]->link)."\n";
                $feed.= "            ".$this->items[$i]->getDescription()."\n";
     
                if($this->items[$i]->author!=""){
                    $feed.= "            ".htmlspecialchars($this->items[$i]->author)."\n";
                }
                /*
                 // on hold
                 if($this->items[$i]->source!=""){
                 $feed.= "            ".htmlspecialchars($this->items[$i]->source)."\n";
                 }
                 */
                if($this->items[$i]->category!=""){
                    $feed.= "            ".htmlspecialchars($this->items[$i]->category)."\n";
                }
                if($this->items[$i]->comments!=""){
                    $feed.= "            ".htmlspecialchars($this->items[$i]->comments)."\n";
                }
                if($this->items[$i]->date!=""){
                    $itemDate=new FeedDate($this->items[$i]->date);
                    $feed.= "            ".htmlspecialchars($itemDate->rfc822())."\n";
                }
                if($this->items[$i]->guid!=""){
                    $feed.= "            ".htmlspecialchars($this->items[$i]->guid)."\n";
                }
                $feed.= $this->_createAdditionalElements($this->items[$i]->additionalElements,"        ");
                $feed.= "       
    \n";
            }
            $feed.= "   
    \n";
            $feed.= "
    \n";
            return $feed;
        }
    }
     
    class RSSCreator20 extends RSSCreator091{
     
        function RSSCreator20(){
            parent::_setRSSVersion("2.0");
        }
    }


    使用示例:

    复制代码 代码如下:

    header('Content-Type:text/html; charset=utf-8');
    $db=mysql_connect('127.0.0.1','root','123456');
    mysql_query("set names utf8");
    mysql_select_db('dbname',$db);
    $brs=mysql_query('select * from article order by add_time desc limit 0,10',$db);
    $rss=new UniversalFeedCreator();
    $rss->title="页面标题";
    $rss->link="网址http://";
    $rss->description="rss标题";
    while($rowbrs=mysql_fetch_array($brs)){
        $item=new FeedItem();
        $item->title =$rowbrs['subject'];
        $item->link='http://www.bkjia.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。

    Statement
    The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
    php怎么把负数转为正整数php怎么把负数转为正整数Apr 19, 2022 pm 08:59 PM

    php把负数转为正整数的方法:1、使用abs()函数将负数转为正数,使用intval()函数对正数取整,转为正整数,语法“intval(abs($number))”;2、利用“~”位运算符将负数取反加一,语法“~$number + 1”。

    php怎么实现几秒后执行一个函数php怎么实现几秒后执行一个函数Apr 24, 2022 pm 01:12 PM

    实现方法:1、使用“sleep(延迟秒数)”语句,可延迟执行函数若干秒;2、使用“time_nanosleep(延迟秒数,延迟纳秒数)”语句,可延迟执行函数若干秒和纳秒;3、使用“time_sleep_until(time()+7)”语句。

    php怎么除以100保留两位小数php怎么除以100保留两位小数Apr 22, 2022 pm 06:23 PM

    php除以100保留两位小数的方法:1、利用“/”运算符进行除法运算,语法“数值 / 100”;2、使用“number_format(除法结果, 2)”或“sprintf("%.2f",除法结果)”语句进行四舍五入的处理值,并保留两位小数。

    php怎么根据年月日判断是一年的第几天php怎么根据年月日判断是一年的第几天Apr 22, 2022 pm 05:02 PM

    判断方法:1、使用“strtotime("年-月-日")”语句将给定的年月日转换为时间戳格式;2、用“date("z",时间戳)+1”语句计算指定时间戳是一年的第几天。date()返回的天数是从0开始计算的,因此真实天数需要在此基础上加1。

    php怎么替换nbsp空格符php怎么替换nbsp空格符Apr 24, 2022 pm 02:55 PM

    方法:1、用“str_replace(" ","其他字符",$str)”语句,可将nbsp符替换为其他字符;2、用“preg_replace("/(\s|\&nbsp\;||\xc2\xa0)/","其他字符",$str)”语句。

    php怎么判断有没有小数点php怎么判断有没有小数点Apr 20, 2022 pm 08:12 PM

    php判断有没有小数点的方法:1、使用“strpos(数字字符串,'.')”语法,如果返回小数点在字符串中第一次出现的位置,则有小数点;2、使用“strrpos(数字字符串,'.')”语句,如果返回小数点在字符串中最后一次出现的位置,则有。

    php字符串有没有下标php字符串有没有下标Apr 24, 2022 am 11:49 AM

    php字符串有下标。在PHP中,下标不仅可以应用于数组和对象,还可应用于字符串,利用字符串的下标和中括号“[]”可以访问指定索引位置的字符,并对该字符进行读写,语法“字符串名[下标值]”;字符串的下标值(索引值)只能是整数类型,起始值为0。

    php怎么读取字符串后几个字符php怎么读取字符串后几个字符Apr 22, 2022 pm 08:31 PM

    在php中,可以使用substr()函数来读取字符串后几个字符,只需要将该函数的第二个参数设置为负值,第三个参数省略即可;语法为“substr(字符串,-n)”,表示读取从字符串结尾处向前数第n个字符开始,直到字符串结尾的全部字符。

    See all articles

    Hot AI Tools

    Undresser.AI Undress

    Undresser.AI Undress

    AI-powered app for creating realistic nude photos

    AI Clothes Remover

    AI Clothes Remover

    Online AI tool for removing clothes from photos.

    Undress AI Tool

    Undress AI Tool

    Undress images for free

    Clothoff.io

    Clothoff.io

    AI clothes remover

    AI Hentai Generator

    AI Hentai Generator

    Generate AI Hentai for free.

    Hot Article

    R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
    2 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
    Repo: How To Revive Teammates
    4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
    Hello Kitty Island Adventure: How To Get Giant Seeds
    4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌

    Hot Tools

    MantisBT

    MantisBT

    Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

    PhpStorm Mac version

    PhpStorm Mac version

    The latest (2018.2.1) professional PHP integrated development tool

    VSCode Windows 64-bit Download

    VSCode Windows 64-bit Download

    A free and powerful IDE editor launched by Microsoft

    Notepad++7.3.1

    Notepad++7.3.1

    Easy-to-use and free code editor

    Atom editor mac version download

    Atom editor mac version download

    The most popular open source editor