jQuery toggle
jQuery .toggle()
by Nirvanachain
HTML
<select class="selectOne" onchange="selectChange()";>
<option value=""></option>
<option value="1">1</option>
<option value="2">2</option>
</select>
<br />
<select class="selectTwo" disabled="disabled">
<option value=""></option>
</select>
<br />
<select class="selectThree" disabled="disabled">
<option value=""></option>
<option value="A">A</option>
<option value="B">B</option>
</select>
CSS
.selectOne {
margin:20px 0 0 20px;
width:50px;
}
.selectTwo{
margin:20px 0 0 20px;
width:50px;
}
.selectThree {
display:none;
margin:20px 0 0 20px;
width:50px;
}
JavaScript
function selectChange() {
if ($(".selectOne").attr('value') != ""){
$(".selectThree").toggle();
}
}