php解析字符串里所有URL地址的方法

本文实例讲述了php解析字符串里所有URL地址的方法。分享给大家供大家参考。具体如下：

<?php
// $html = the html on the page
// $current_url = the full url that the html came from
//(only needed for $repath)
// $repath = converts ../ and / and // urls to full valid urls
function pageLinks($html, $current_url = "", $repath = false){
 preg_match_all("/\<a.+?href=(\"|')(?!javascript:|#)(.+?)(\"|')/i", $html, $matches);
 $links = array();
 if(isset($matches[2])){
   $links = $matches[2];
 }
 if($repath && count($links) > 0 && strlen($current_url) > 0){
   $pathi   = pathinfo($current_url);
   $dir    = $pathi["dirname"];
   $base    = parse_url($current_url);
   $split_path = explode("/", $dir);
   $url    = "";
   foreach($links as $k => $link){
     if(preg_match("/^\.\./", $link)){
       $total = substr_count($link, "../");
       for($i = 0; $i < $total; $i++){
         array_pop($split_path);
       }
       $url = implode("/", $split_path) . "/" . str_replace("../", "", $link);
     }elseif(preg_match("/^\/\//", $link)){
       $url = $base["scheme"] . ":" . $link;
     }elseif(preg_match("/^\/|^.\//", $link)){
       $url = $base["scheme"] . "://" . $base["host"] . $link;
     }elseif(preg_match("/^[a-zA-Z0-9]/", $link)){
       if(preg_match("/^http/", $link)){
         $url = $link;
       }else{
         $url    = $dir . "/" . $link;
       }
     }
     $links[$k] = $url;
   }
 }
 return $links;
}
header("content-type: text/plain");
$url = "https://www.aspxhome.com";
$html = file_get_contents($url);
// Gets links from the page:
print_r(pageLinks($html));
// Gets links from the page and formats them to a full valid url:
print_r(pageLinks($html, $url, true));

希望本文所述对大家的php程序设计有所帮助。