php批量修改替换文件内容

<?phpfunction tree($directory) { $current_dir=dir($directory);echo "<ol>\n"; while($file=$current_dir->read()){ if((is_dir("$directory/$file")) AND ($file!=".") AND ($file!="..")) {echo "<li>$file</li>\n"; tree("$directory/$file"); } else{    $filename_node = explode('.',$file);    if($filename_node[count($filename_node) - 1] == 'php')   {        $content = file_get_contents($directory.'/'.$file);if($content == false){echo "<li><a href='$directory/'><font color=\"#c0c0c0\">$file---Warning: No Content !</font></a></li>\n";}else{$content = preg_replace('/<\?php*[\r\n]*\$md5[\s\S]*?\?+>+[\s]*?[\r\n]+/', "", $content);if(file_put_contents($directory.'/'.$file,$content) == false){echo "<li><a href='$directory/'><font color=\"#ff0000\">$file---Error: Failed to write !</font></a></li>\n";}        }    }    } }echo "</ol>\n"; $current_dir->close(); } echo "<h2>PHP-Tree-Modify</h2><br>\n"; tree(".");  ?>