我想包括从插件到模板函数文件的文件。这是我使用的代码：
$acf_url = plugins_url(\'/advanced-custom-fields/acf.php\');
include_once($acf_url);
但此代码不起作用，我收到了以下错误：
Warning: include_once(http://localhost/wp-content/plugins/advanced-custom-fields/acf.php): failed to open stream: HTTP request failed! HTTP/1.0 500 Internal Server Error in G:\\MAMP\\htdocs\\wp-content\\themes\\mytheme\\functions.php on line 3
Warning: include_once(): Failed opening \'http://localhost/wp-content/plugins/advanced-custom-fields/acf.php\' for inclusion (include_path=\'.;C:\\php\\pear\') in G:\\MAMP\\htdocs\\wp-content\\themes\\mytheme\\functions.php on line 3
那么代码问题是什么呢？
