先了解一下什么是抓取？

抓取就是网络爬虫，也就是人们常说的网络蜘蛛（spider）。是搜索引擎的一个重要组成部分，按照一定的逻辑和算法抓取和下载互联网上的信息和网页。一般的爬虫从一个start url开始，按照一定的策略开始爬取，把爬取到的新的url放入爬取队列中，然后进行新一轮的爬取，直到抓取完毕为止。

PHPCrawler是一个国外开源的爬虫系统，它的源码托管在sourceforge里，这是它的下载地址：点击打开链接

，根据自己电脑里安装的PHP版本选择合适的版本下载。下载完毕之后，解压到服务器网站根目录下，复制example.php文件，并重命名。

<?php// It may take a whils to crawl a site ...
set_time_limit(10000);// Inculde the phpcrawl-mainclass
include("libs/PHPCrawler.class.php");// Extend the class and override the handleDocumentInfo()-method
class MyCrawler extends PHPCrawler
{//在这里解析页面内容function handleDocumentInfo($DocInfo) {// Just detect linebreak for output ("\n" in CLI-mode, otherwise "<br>").if (PHP_SAPI == "cli") $lb = "\n";else $lb = "<br />";// Print the URL and the HTTP-status-Codeecho "Page requested: ".$DocInfo->url." (".$DocInfo->http_status_code.")".$lb;// Print the refering URLecho "Referer-page: ".$DocInfo->referer_url.$lb;// Print if the content of the document was be recieved or notif ($DocInfo->received == true)echo "Content received: ".$DocInfo->bytes_received." bytes".$lb;elseecho "Content not received".$lb; // Now you should do something with the content of the actual// received page or file ($DocInfo->source), we skip it in this example //echo $DocInfo->source;//echo $lb;$url=$DocInfo->url;$pat="/http:\/\/www\.kugou\.com\/yy\/special\/single\/\d+\.html/";if(preg_match($pat,$url)>0){$this->parseSonglistDetail($DocInfo);}flush();} public function parseSonglistDetail($DocInfo){$songlistArr=array();$songlistArr['raw_url']=$DocInfo->url;$content=$DocInfo->content;//名称$matches=array();$pat="/<span>名称：<\/span>([^(<br)]+)<br \/>/";$res=preg_match($pat, $content,$matches);if($res>0){$songlistArr['title']=$matches[1];}else{$songlistArr['title']="";print "error:get title fail<br/>";}//创建人$matches=array();$pat="/<span>创建人：<\/span>([^(<br)]+)<br \/>/";$res=preg_match($pat, $content,$matches);if($res>0){$songlistArr['creator']=$matches[1];}else{$songlistArr['creator']="";print "error:get creator fail<br/>";}//创建时间$matches=array();$pat="/<span>更新时间：<\/span>([^(<br)]+)<br \/>/";$res=preg_match($pat, $content,$matches);if($res>0){$songlistArr['create_date']=$matches[1];}else{$songlistArr['create_date']="";print "error:get create_date fail<br/>";}//简介$matches=array();$pat="/<span>简介：<\/span>([^(<\/p)]*)<\/p>/";$res=preg_match($pat, $content,$matches);if($res>0){$songlistArr['info']=$matches[1];}else{$songlistArr['info']="";print "error:get info fail<br/>";}//歌曲$matches=array();$pat="/<a title=\"([^\"]+)\" hidefocus=\"/";$res=preg_match_all($pat, $content,$matches);if($res>0){$songlistArr['songs']=array();for($i=0;$i<count($matches[1]);$i++){$song_title=$matches[1][$i];array_push($songlistArr['songs'],array('title'=>$song_title));}}else{$songlistArr['song']="";print "error:get song fail<br/>";}echo "<pre>";print_r($songlistArr);echo "</pre>";$this->saveSonglist($songlistArr);}public function saveSonglist($songlistArr){//连接数据库$conn=mysql_connect("localhost","root","root");mysql_select_db("songlist",$conn);mysql_query("set names utf8");$songlist=array();$songlist['title']=mysql_escape_string($songlistArr['title']);$songlist['create_time']=mysql_escape_string($songlistArr['create_date']);$songlist['creator']=mysql_escape_string($songlistArr['creator']);$songlist['raw_url']=mysql_escape_string($songlistArr['raw_url']);$songlist['info']=mysql_escape_string($songlistArr['info']);$sql="insert into songlist set"."title=''".$songlist['title']."'".",creat_time=''".$songlist['create_time']."'".",creator=''".$songlist['creator']."'".",raw_url=''".$songlist['raw_url']."'".",info=''".$songlist['info']."';";mysql_query($sql,$conn);$songlist_id=mysql_insert_id();foreach($songlistArr['songs'] as $song){$title=mysql_escape_string($song['title']);$sql="insert into song set title='".$title."'" .",songlist_id=".$songlist_id.";";mysql_query($sql);}mysql_close($conn);}
}// Now, create a instance of your class, define the behaviour
// of the crawler (see class-reference for more options and details)
// and start the crawling-process.
//创建一个爬虫
$crawler = new MyCrawler();
//设置一个开始的连接
// URL to crawl
$start_url="www.kugou.com/yy/special/index/1-0-2.html";
$crawler->setURL($start_url);
//设置内容的类型
// Only receive content of files with content-type "text/html"
$crawler->addContentTypeReceiveRule("#text/html#");
//忽略图片，设置那些连接不需要下载//每一个精选集的连接
$crawler->addURLFollowRule("#http://www\.kugou\.com/yy/special/single/\d+\.html# i");//i 忽略大小写
//精选集页面的链接 下一页
$crawler->addURLFollowRule("#http://www\.kugou\.com/yy/special/index/\d+-0-2.html# i");// Ignore links to pictures, dont even request pictures
$crawler->addURLFilterRule("#\.(jpg|jpeg|gif|png)$# i");// Store and send cookie-data like a browser does
$crawler->enableCookieHandling(true);// Set the traffic-limit to 1 MB (in bytes,
// for testing we dont want to "suck" the whole site)
//数据内容的容量，多少m，0是无限的
$crawler->setTrafficLimit(1000 * 1024);// Thats enough, now here we go
$crawler->go();// At the end, after the process is finished, we print a short
// report (see method getProcessReport() for more information)
$report = $crawler->getProcessReport();if (PHP_SAPI == "cli") $lb = "\n";
else $lb = "<br />";echo "Summary:".$lb;
echo "Links followed: ".$report->links_followed.$lb;
echo "Documents received: ".$report->files_received.$lb;
echo "Bytes received: ".$report->bytes_received." bytes".$lb;
echo "Process runtime: ".$report->process_runtime." sec".$lb;
?>