使用PHP简单网页抓取和内容分析

没事的时候想抓取点网页看看，也不太懂，只是玩玩，写了点代码，聊以娱乐。

稍微有点意义的函数是：get_content_by_socket(), get_url(), get_content_url(), get_content_object几个函数，也许能够给你点什么想法。

<?php

//获取所有内容url保存到文件
function get_index($save_file,$prefix="index_"){
$count = 68;
$i = 1;
if (file_exists($save_file)) @unlink($save_file);
$fp = fopen($save_file,"a+") or die("Open ".$save_file ." failed");
while($i<$count){
$url = $prefix . $i.".htm";
echo "Get ".$url ."...";
$url_str = get_content_url(get_url($url));
echo " OK/n";
fwrite($fp,$url_str);
++$i;
}
fclose($fp);
}

//获取目标多媒体对象
function get_object($url_file,$save_file,$split="|--:**:--|"){
if (!file_exists($url_file)) die($url_file." not exist");
$file_arr =file($url_file);
if (!is_array($file_arr) || empty($file_arr)) die($url_file." not content");
$url_arr = array_unique($file_arr);
if (file_exists($save_file)) @unlink($save_file);
$fp = fopen($save_file,"a+") or die("Open save file ".$save_file ." failed");
foreach($url_arr as$url){
if (empty($url)) continue;
echo "Get ".$url ."...";
$html_str =get_url($url);
echo $html_str;
echo $url;
exit;
$obj_str = get_content_object($html_str);
echo " OK/n";
fwrite($fp,$obj_str);
}
fclose($fp);
}

//遍历目录获取文件内容
function get_dir($save_file,$dir){
$dp = opendir($dir);
if (file_exists($save_file)) @unlink($save_file);
$fp = fopen($save_file,"a+") or die("Open save file ".$save_file ." failed");
while(($file =readdir($dp)) !=false){
if ($file!="."&& $file!=".."){
echo "Read file ".$file ."...";
$file_content =file_get_contents($dir. $file);
$obj_str = get_content_object($file_content);
echo " OK/n";
fwrite($fp,$obj_str);
}
}
fclose($fp);
}


//获取指定url内容
function get_url($url){
$reg = '/^http:////[^//].+$/';
if (!preg_match($reg,$url)) die($url." invalid");
$fp = fopen($url,"r") or die("Open url: ".$url ." failed.");
while($fc =fread($fp,8192)){
$content .=$fc;
}
fclose($fp);
if (empty($content)){
die("Get url: ".$url ." content failed.");
}
return $content;
}

//使用socket获取指定网页
function get_content_by_socket($url,$host){
$fp = fsockopen($host,80) or die("Open ".$url ." failed");
$header = "GET /".$url." HTTP/1.1/r/n";
$header .= "Accept: */*/r/n";
$header .= "Accept-Language: zh-cn/r/n";
$header .= "Accept-Encoding: gzip, deflate/r/n";
$header .= "User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; Maxthon; InfoPath.1; .NET CLR 2.0.50727)/r/n";
$header .= "Host: ". $host."/r/n";
$header .= "Connection: Keep-Alive/r/n";
//$header .= "Cookie: cnzz02=2; rtime=1; ltime=1148456424859; cnzz_eid=56601755-/r/n/r/n";
$header .= "Connection: Close/r/n/r/n";

fwrite($fp,$header);
while (!feof($fp)) {
$contents .=fgets($fp,8192);
}
fclose($fp);
return $contents;
}


//获取指定内容里的url
function get_content_url($host_url,$file_contents){

//$reg = '/^(#|javascript.*?|ftp:////.+|http:////.+|.*?href.*?|play.*?|index.*?|.*?asp)+$/i';
//$reg = '/^(down.*?/.html|/d+_/d+/.htm.*?)$/i';
$rex = "/([hH][rR][eE][Ff])/s*=/s*['/"]*([^>'/"/s]+)[/"'>]*/s*/i";
$reg = '/^(down.*?/.html)$/i';
preg_match_all ($rex,$file_contents,$r);
$result = ""; //array();
foreach($r as $c){
if (is_array($c)){
foreach($c as$d){
if (preg_match($reg,$d)){ $result .= $host_url . $d."/n"; }
}
}
}
return $result;
}

//获取指定内容中的多媒体文件
function get_content_object($str,$split="|--:**:--|"){
$regx = "/href/s*=/s*['/"]*([^>'/"/s]+)[/"'>]*/s*(<b>.*?<//b>)/i";
preg_match_all($regx,$str, $result);

if (count($result) ==3){
$result[2] =str_replace("<b>多媒体： ","", $result[2]);
$result[2] =str_replace("</b>","", $result[2]);
$result = $result[1][0] .$split .$result[2][0] . "/n";
}
return $result;
}

?>