hi, Try out the following code 
print "Content-type:text/html\n\n";
print << 'JavaScript';
<script language='javascript'>
function alertselected(selectobj){
ss=selectobj.selectedIndex
if(ss == 2){
document.getElementById('new').style.display='block';
}
else{
document.getElementById('new').style.display='none';
}
}
</script>
JavaScript
print "<html><body><form name=frm1>";
print "<select name=os onChange='alertselected(this)'>
<option value='redhat'>Redhat</option>
<option value='centos'>Centos</option>
<option value='others'>Others</option>
</select>";
print "<input id=new type=text name=newos style='display: none;'></for
+m></body></html>";

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In reply to Re: How do I display a textbox only if a certain value is selected from a dropdown list by sanku
in thread How do I display a textbox only if a certain value is selected from a dropdown list by wishartz

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