Dynamic visibilty

<script language="javascript">
function changeVisibility(val){
// If the value of the drop down is company then go ahead and start clearing some of the form fields
if(val == "company"){
// clear the inputs you want
document.getElementById("input1").style.visibility = "hidden";
// or do it this way
document.getElementById("input1").style.display = "none"
return;
}
// If this does not have the value of company, keep the style
document.getElementById("input1").style.display = "";
return;
}
</script>
 
<select name="dropdown" onChange="changeVisibility(this.value)">
 <option value="company">company</option>
 <option value="house">house</option>
</select>