不知道樓主是不是這哥意思,看下例子.
<html>
<head>
<script>
function creatSel(){
var v1=document.getElementById("sel").value;
var sel=document.createElement("select");
//var sel=document.getElementsByName("sel")[0];
var item = new Option("+"+v1,"+"+v1);
var item1 = new Option("-"+v1,"-"+v1);
sel.options.add(item);
sel.options.add(item1);
document.body.appendChild(sel);
}
</script>
</head>
<body>
<select id="sel" onchange="creatSel()" name="sel">
<option value="1">v1</option>
<option value="2">v2</option>
<option value="3">v3</option>
<option value="4">v4</option>
</select><body>
<html>
<html>
<head>
<script>
function creatSel(){
var v1=document.getElementById("sel").value;
var sel=document.createElement("select");
//var sel=document.getElementsByName("sel")[0];
var item = new Option("+"+v1,"+"+v1);
var item1 = new Option("-"+v1,"-"+v1);
sel.options.add(item);
sel.options.add(item1);
document.body.appendChild(sel);
}
</script>
</head>
<body>
<select id="sel" onchange="creatSel()" name="sel">
<option value="1">v1</option>
<option value="2">v2</option>
<option value="3">v3</option>
<option value="4">v4</option>
</select><body>
<html>
解决方案 »
免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货