hai ragione su tutti i fronti

mannaggia all'ignoranza

1)
cambiato id con Id

2)
cambiato else finale

ma il risultato non cambia, ho sempre quel malefico errore sulla riga:

document.getElementByld('hiddenOpt_1').style.visib ility = "visible";

scusa se approfitto ma riposto nuovamente il code:


<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
</HEAD>

<BODY>
<form name="form1">
<table border="0" cellspacing="2" cellpadding="0" width="80%"><tr><td>
<select name="bambini" onChange="DropDown();">
<option value="0"></option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
</td><td>
<div Id="hiddenOpt_1" style="visibility:hidden;">
<select name="eta_bambini_1">
<option value="0-2">0-2</option>
<option value="2-6">2-6</option>
<option value="6-12">6-12</option>
</select>
</div>
</td><td>
<div Id="hiddenOpt_2" style="visibility:hidden;">
<select name="eta_bambini_2">
<option value="0-2">0-2</option>
<option value="2-6">2-6</option>
<option value="6-12">6-12</option>
</select>
</div>
</td><td>
<div Id="hiddenOpt_3" style="visibility:hidden;">
<select name="eta_bambini_3">
<option value="0-2">0-2</option>
<option value="2-6">2-6</option>
<option value="6-12">6-12</option>
</select>
</div>
<script>
function DropDown(){
if(document.form1.bambini.options[document.form1.bambini.selectedIndex].value=="1"){
document.getElementByld('hiddenOpt_1').style.visib ility = "visible";
} else if(document.form1.bambini.options[document.form1.bambini.selectedIndex].value=="2"){
document.getElementByld('hiddenOpt_1').style.visib ility = "visible";
document.getElementByld('hiddenOpt_2').style.visib ility = "visible";
} else if(document.form1.bambini.options[document.form1.bambini.selectedIndex].value=="3"){
document.getElementByld('hiddenOpt_1').style.visib ility = "visible";
document.getElementByld('hiddenOpt_2').style.visib ility = "visible";
document.getElementByld('hiddenOpt_3').style.visib ility = "visible";
} else {
document.getElementByld('hiddenOpt_1').style.visib ility = "hidden";
document.getElementByld('hiddenOpt_2').style.visib ility = "hidden";
document.getElementByld('hiddenOpt_3').style.visib ility = "hidden";
}
}
</script>
</td></tr></table>
</BODY>
</HTML>