php判断是否引入某文件

Code：

/* 判断是否引入了公共文件demo.php */
$include_files = get_included_files();
$include_files_exist = 0 ;
foreach($include_files as $include_files_val){
    if(strpos($include_files_val,'demo.php') !== false ){
        $include_files_exist = 1;
    }
}
if($include_files_exist != 1){
    include_once('demo.php');
}

Command：

get_included_files();

strpos()

include_once();

其实，当时是因为重复引入同一文件引起报错，解决办法很简单，直接改为include_once() 或 require_once() 就OK。