/*
@desc：获取路径信息
@param path 传入路径，如a/b/c.jpg
@return info dir:路径，name:文件名，suffix:后缀名 
*/
function fileinfo($path){
$dir = dirname($path);
$name = basename($path);
$suffix = pathinfo($path,PATHINFO_EXTENSION);
$info = array(
        'dir'=>$dir,
        'name'=>$name,
        'suffix'=>$suffix
    );
return $info;
}

$ret = fileinfo('a/b/c.jpg');
var_dump($ret);

array(3) {
["dir"]=>
string(3) "a/b"
["name"]=>
string(5) "c.jpg"
["suffix"]=>
string(3) "jpg"
}