php解析字符串裡所有URL地址的方法

 具體如下：

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 <?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 = "http://www.jb51.net"; $html = file_get_contents($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));