Her er et hurtigt eksempel, der skulle være til at bygge lidt videre på.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "
http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="
http://www.w3.org/1999/xhtml" >
<head>
<title>Untitled Page</title>
<script type="text/javascript" src="
http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script> <script type="text/javascript">
var lineMarkup = "<fieldset><input type='text' /></fieldset>";
$(document).ready(function () {
$("#selectLines").val(0);
$("#selectLines").change(function () {
$("#lines").html("");
for (i = 0; i < $("#selectLines").val(); i++) {
$("#lines").append($(lineMarkup).attr('id', 'line' + (i + 1)));
}
});
$("form").submit(function () {
var errors = $("input[value=]:text").length;
if (errors == 0) {
alert("weeee");
} else {
alert("alle linier skal udfyldes, ellers fjern.")
}
});
});
</script>
</head>
<body>
<form action="#" method="get">
<select id="selectLines">
<option value="0">ingen..</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
<div id="lines">
</div>
<input type="submit" />
</form>
</body>
</html>