Dropdown reading array and onclick

Hello, i am all new to this kind of stuff and i didnt find any topic yet about it because i do not really know how to call this problem. So if there are any solutions yet i am sorry for opening a new topic.

I want a dropdown navigation, that read its content out of an array.

thats what i got so far and it works.

[CODE]<?
echo ‘<SELECT name=bild>’;

foreach ($zahl_array as $key => $value)
{
echo ‘<OPTION value=’.$value.’> ‘.$value.”;
}
echo ‘</select>’;
?>
[/CODE]

$zahl_array is reading the array content out of a .txt file.

Now the problem is that i want something to happen when you change/click on one link in the dropdown.

Above this code, there is a table with an randomly generated Image.

[CODE]
$zahl_array = file(‘zahl.txt’);
$num = rand(0, count($zahl_array) – 1);
$zahl = $zahl_array[$num];
…html…<img src=”/images/<? echo $zahl; ?>.jpg”>…html…
[/CODE]

Now if the user chooses one link in the dropdown it should change the Image above to the one that the user choosed.

Sry for bad english i am from germany

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