<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Example</title>
<style type="text/css">
#input input{display:none;}
</style>
</head>
<body>
<select name="PB2001" onchange="fifeno(this)">
<option value="?">?</option>
<option value="no">no</option>
<option value="two">two</option>
<option value="(BG) NFF LO">(BG) NFF LO</option>
</select>
<div id="input">
<input name="input1" value="Появился1">
<input name="input2" value="Появился2">
</div>
<script type="text/javascript">
function arrayInput() {
return document.getElementById('input').getElementsByTagName('input');
}
function inputStyle(key) {
return arrayInput()[key].style;
}
function inputToggle(val) {
for(var i in arrayInput()) {
if(true===val || i==val) {
inputStyle(i).display='block';
} else {
inputStyle(i).display='';
}
}
}
function fifeno(self) {
if('no'==self.value) {
inputToggle(0);
} else if('?'==self.value) {
inputToggle();
} else if('two'==self.value) {
inputToggle(true);
} else {
inputToggle(1);
}
}
</script>
</body>
</html>