---恢復內容開始---

<select id = "a1" onchange = "addOption()"></select>

<select id = "a2"></select>

<script type = "text/javascript">

var city = new Array;
city[‘江蘇‘] = [‘南京‘,‘上海‘, ‘連雲港‘, ‘蘇州‘, ‘鎮江‘,‘泰州‘,‘南通‘,‘淮安‘];
city[‘山東‘] = [‘青島‘,‘煙臺‘, ‘濟南‘,‘曲阜‘,‘德州‘,‘濱州‘,‘臨沂‘,‘菏澤‘];
city[‘湖南‘] = [‘長沙‘,‘株洲‘,‘湘潭‘,‘嶽陽‘,‘婁底‘,‘常德‘,‘懷化‘,‘張家界‘];
function allCity() {
var select1 = document.getElementById("a1");
for(var i in city) { //這裏註意遍歷數組的寫法
select1.add(new Option(i, i), null);
}
addOption(); // 初始化選項
}
function addOption() {
var select2 = document.getElementById("a2");
var select1 = document.getElementById("a1").value;
select2.length = 0; //每次都先清空一下市級菜單
if(select1 != ‘請選擇省份‘) {
for(var i in city[select1 ]) {
select2.add(new Option(city[select1][i], city[select1][i]), null);
}
}else if (sheng == ‘請選擇省份‘){
select2.length = 0;
select2.add(new Option("請選擇城市", "請選擇城市"), null);
}
}
window.onload = allCity();

</script>

---恢復內容結束---

JavaScript 數組 二級聯動下拉列表