$ _FILES中的子数组

I have 2 associative arrays within $_Files and cannot figure out how to loop through them. The following is the print_r($_FILES) result:

Array
(
    [userfile] => Array
        (
            [name] => Lilly-Pond-Leo-Kenney.jpg
            [type] => image/jpeg
            [tmp_name] => C:\wamp\tmp\php189.tmp
            [error] => 0
            [size] => 429950
        )

    [userfile1] => Array
        (
            [name] => LK-3-women.jpg
            [type] => image/jpeg
            [tmp_name] => C:\wamp\tmp\php18A.tmp
            [error] => 0
            [size] => 79391
        )

)

I cannot figure out how to loop from [userfile] to [userfile1]. Any help will be appreciated

foreach($_FILES as $file)
{
  //use this loop and remove print_r();
  print_r($file);
}