How to use an array to auto fill a form?

[sitingduck]

I used this code to pull info from the database and into the array.

$stu_quary = "SELECT `uname` FROM `user` WHERE level = 'Normal' AND class = '".$_SESSION['class']."'"; 
	$stu_names=mysql_query($stu_quary);
	$stuArr=array();
	while($get_stu_info =mysql_fetch_assoc($stu_names)) 
	{ 
	$n = 0;
    $stuArr[] = $get_stu_info['uname']; 
	$_SESSION['selected_s'] = current($stuArr);
	}

I then use the session to auto full the form.
When submited I want the next value in the array to be applied to th session.

if(isset($_POST['postComment']))
{
	$query = "INSERT INTO ".$_POST['student_name']."_".$_POST['class']." SET name='".$_POST['student_name']."',title='".$_POST['student_name']." Report for Week: ".$_POST['week']."',subject='".$_POST['subject']."',class='".$_POST['class']."',author='".$_POST['author']."',week='".$_POST['week']."',par='".$_POST['par']."',beh='".$_POST['beh']."',lis='".$_POST['lis']."',spe='".$_POST['spe']."',mot='".$_POST['mot']."',ret='".$_POST['ret']."',comments='".$_POST['comment']."',";
	$query .="date_posted=NOW(),categoryID='".$_POST['select']."',artchild='0'";
	if(!mysql_query($query))
	{		
		echo mysql_error();
	}
	else
	{
		$_SESSION['selected_s'] = next($stuArr);
	}

I use this code but it only works for the first time a form is submited afterwards the value stays the same.
Is is next() the right function?
What would be the bst way to achieve this?
Thanks in advance.

[mfaisalwarraich]

i think u need to get relative values. try with this one. i have altered this function to get its relative values instead of keys.:

function array_key_relative($array, $current_key, $offset = 1)
{
	 // create key map
	 $keys = array_values($array);
	 // find current key
	 $current_key_index = array_search($current_key, $keys);
	 // return desired offset, if in array, or false if not
	 if(isset($keys[$current_key_index + $offset]))
	 {
		 return $keys[$current_key_index + $offset];
	 }
	 return false;
}
//next value :
array_key_relative($$stuArr,$current_value,1);
//previous value
array_key_relative($$stuArr,$current_value,-1);