根据不同的下拉值，出现相应的文本输入框
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">;
<html xmlns="http://www.w3.org/1999/xhtml">;
<head>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@taglib prefix="s" uri="/struts-tags"%>
<title>无标题文档</title>
<script language="javascript">
function $(obj){return document.getElementById(obj);}
function show(objid) {$(objid).style.display='inline';}
function hidden(objid) {$(objid).style.display='none';}
function doit(){
var sel_val=$('sel').value;
if (sel_val=='') {hidden('a1');hidden('a2');}
if (sel_val==0) {hidden('a1');hidden('a2');}
if (sel_val==1) {show('a1');hidden('a2');}
if (sel_val==2) {show('a2');hidden('a1');}
}
</script>
</head>
<body>
<select name="sel" id="sel" onchange="javascript:doit();">
<option selected="selected">请选择</option>
<option value="0">不要输入框</option>
<option value="1">输入框1</option>
<option value="2">输入框2</option>
</select>
<input value="输入框1" type="text" name="a1" id="a1" style="display:none;" />
<input value="输入框2" type="text" name="a2" id="a2" style="display:none;" />
<br />
<br />
</body>
</html>
