以下是html代碼：
複製代碼代碼如下:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT="">
</HEAD>
<!-- by sundful starting-->
<BODY>
<script language="JavaScript">
var subcat = new Array();
subcat[0] = new Array('中文','英語','英語')
subcat[1] = new Array('中文','法語','法語')
subcat[2] = new Array('英語','中文','中文')
subcat[3] = new Array('法語','中文','中文')
function changeselect1(locationid)
{
document.form1.s2.length = 0; //初始化下拉列表清空下拉數據
document.form1.s2.options[0] = new Option('==請選擇==',''); //給第一個值
for (i=0; i<subcat.length; i++) //legth=20
{
if (subcat[i][0] == locationid) //[0] [1] 第一列第二列
{document.form1.s2.options[document.form1.s2.length] = new Option(subcat[i][1], subcat[i][2]);} //建立option
//第一次length=1 因為有==請選擇==
//i=9時length= 10 值有11個因為從0數起subcat[i][0] == locationid屏蔽了再寫
}
}
</script>
<form name="form1" method="post" runat="server">
二級聯動：
<select name="s1" onChange="changeselect1(this.value)">
<option>==請選擇==</option>
<option value="中文">中文</option>
<option value="英語">英語</option>
<option value="英語">法語</option>
</select>
<select name="s2">
<option>==請選擇==</option>
</select>
</form>
<!-- by sundful ending-->
</BODY>
</HTML>