php从给定url获取文件扩展名的方法

<?php/** * 给定url，获取文件后缀 * @param string $url * @return string */function getUrlPostfix ($url){  $url_arr = explode('.', $url);  $postfix = $url_arr[count($url_arr) - 1];  $substr = substr($postfix, 0, 3);  return $substr;}$url = "//www.VeVB.COm/index.html?id=1";$str = getUrlPostfix($url);echo $str . "/n";