排序数组[0]

Array ( [0] => wilson ) 
Array ( [0] => umkk )
Array ( [0] => audiok ) 
Array ( [0] => Futurama ) 

I have the above users array, i'm trying to sort it alphabetically so the result looks like this

audiok
futurama
umkk
wilson

This is my php code from those lines:

$arr1 = explode("
", $users);

            sort ($arr1);
            print_r($arr1);

Why isn't sort () working? It doesnt sort it at all.. what am i doing wrong? I'm new to php programming, i have looked on the php manual and have not been able to sort it after trying all these different examples posted there.

Thanks in advanced.

Edit:

preg_match_all('/control\?user=(.+?)&data/', $linklong, $users) 
$users = $users[1][0];} 

if i print $users all the users are displayed nicely, but when i tried to sort them it tells me is not array, so i took $users, and did explode to create the array... i'm sorry im not very programming savy –

<?php
$array1 = array(0=>'wilson');
$array2 = array(0=>'umkk');
$array3 = array(0=>'audiok');
$array4 = array(0=>'Futurama');

$array = array_merge($array1,$array2,$array3,$array4);
natcasesort($array);
echo '<pre>',print_r($array),'</pre>';

Or if you have text that is 4 names on 4 different lines that you want to explode and sort:

<?php
$text = <<<EOD
wilson
umkk
audiok
Futurama
EOD;

$arr = explode("
",$text);
natcasesort($arr);

echo '<pre>',print_r($arr),'</pre>';

natcasesort() docs

asort() is the function that u need. Following URL contains the example and the output.

http://www.php.net/manual/en/function.asort.php