1.動態創建select

function createSelect(){

var mySelect = document.createElement("select");
mySelect.id = "mySelect";
document.body.appendChild(mySelect);
}

2.添加選項option

function addOption(){

//根據id查找對象，
var obj=document.getElementById('mySelect');

//添加一個選項
obj.add(new Option("文本","值"));
}

3.刪除所有選項option

function removeAll(){
var obj=document.getElementById('mySelect');

obj.options.length=0;

}

4.刪除一個選項option

function removeOne(){
var obj=document.getElementById('mySelect');

//index,要刪除選項的序號，這裡取當前選中選項的序號

var index=obj.selectedIndex;
obj.options.remove(index);
}

5.獲得選項option的值

var obj=document.getElementById('mySelect');

var index=obj.selectedIndex; //序號，取當前選中選項的序號

var val = obj.options[index].value;

6.獲得選項option的文本

var obj=document.getElementById('mySelect');

var index=obj.selectedIndex; //序號，取當前選中選項的序號

var val = obj.options[index].text;

7.修改選項option

var obj=document.getElementById('mySelect');

var index=obj.selectedIndex; //序號，取當前選中選項的序號

var val = obj.options[index]=new Option("新文本","新值");

8.刪除select

function removeSelect(){
var mySelect = document.getElementById("mySelect");
mySelect.parentNode.removeChild(mySelect);
}