out put array as string from form

[screative]

How do I get the below to print out the submitted corresponding parentnav to the submitted filename? The below will print out the filename ok, but when i try to print out $_POST['parentnav'] i get an error.

$filename = array(); 
foreach ($_POST['filename'] as $key=>$value) { 
$filename[$key] = $_POST['parentnav'][$key]; 
print "the file name is".$value;
print "the parentnav is ".???; 
}

[barand]

My crystal ball is a bit misty, I can't see the form that the submitted data comes from to see how the fields are defined.

[screative]

$_POST['parentnav'][$key] .... ahh