从codeigniter tut学习一些代码，下面的preg_match模式让我感到困惑：
preg_match('/js$/', $include)
js之后$的目的是什么？
感谢您总是深思熟虑的回复！
-----完整代码-----
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
* Layouts Class. PHP5 only.
*
*/
class Layouts {
// Will hold a CodeIgniter instance
private $CI;
// Will hold a title for the page, NULL by default
private $title_for_layout = NULL;
// The title separator, ' | ' by default
private $title_separator = ' | ';
public function __construct()
{
$this->CI =& get_instance();
}
public function set_title($title)
{
$this->title_for_layout = $title;
}
public function view($view_name, $params = array(), $layout = 'default')
{
// Handle the site's title. If NULL, don't add anything. If not, add a
// separator and append the title.
if ($this->title_for_layout !== NULL)
{
$separated_title_for_layout = $this->title_separator . $this->title_for_layout;
}
// Load the view's content, with the params passed
$view_content = $this->CI->load->view($view_name, $params, TRUE);
// Now load the layout, and pass the view we just rendered
$this->CI->load->view('laytous/' . $layout, array(
'content_for_layout' => $view_content,
'title_for_layout' => $separated_title_for_layout
));
}
public function add_include($path, $prepend_base_url = TRUE)
{
if ($prepend_base_url)
{
$this->CI->load->helper('url'); // Load this just to be sure
$this->file_includes[] = base_url() . $path;
}
else
{
$this->file_includes[] = $path;
}
return $this; // This allows chain-methods
}
public function print_includes()
{
// Initialize a string that will hold all includes
$final_includes = '';
foreach ($this->includes as $include)
{
// Check if it's a JS or a CSS file
if (preg_match('/js$/', $include))
{
// It's a JS file
$final_includes .= '<script type="text/javascript" src="' . $include . '"></script>';
}
elseif (preg_match('/css$/', $include))
{
// It's a CSS file
$final_includes .= '<link href="' . $include . '" rel="stylesheet" type="text/css" />';
}
return $final_includes;
}
}
}