How would you make a button make the php select the next item in an array?

[k21chrono]

See topic for the question, thank you ahead of time.

[simshaun]

This a homework question?

<?php
$array = array(
'Item 1'
,'Item 2'
,'Item 3'
);

$curIndex = isset($_GET['index']) ? (int) $_GET['index'] : 0;
$nextIndex = $curIndex + 1 >= count($array) || $curIndex < 0 ? 0 : $curIndex + 1;

echo 'Current item: '. $array[$curIndex];
?>
<form method="post" action="?index=<?php echo $nextIndex; ?>">
<input type="submit" name="submit" value="Next Element" />
</form>

[k21chrono]

It is sort of a school question, i get to work independantly in my web design class and i am trying to make sort of a media selectory with a back and forward button.