list / menu – how do I reload a page without loosing input data?

I am making a form.

The user have to choose between two options in a html list/menu.

Depending on what the user choose, I want the page to reload and update another list/menu with results that has with the list option the user just chose.

I have tried with this:

[code]<select name=”vehicle” id=”vehicle” onchange=”javascript:location.reload(true);”>
<option selected=”selected”>——–</option>
<option value=”cars”>Cars</option>
<option value=”mc”>MCs</option>
</select>

<select name=”manufacturer” id=”manufacturer”>
<?php
$vehicle= $_POST[‘vehicle’];
if($vehicle==”cars”)
echo “<option value=”ferrari”>Ferrari</option>”;
echo “<option svalue=”porsche”>Porsche</option>”;
if($vehicle==”mc”)
echo “<option value=”ducati”>Ducati</option>”;
echo “<option value=”suzuki”>Suzuki</option>”;
echo “<option svalue=”sawasaki”>Kawasaki</option>”;
?>
</select>
[/code]

I cannot use action=”” in the form tag because when the user is done he has to press the Next button to get to the next form, so the action tag is already in use.

How can I solve this?

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