js 操作select跟option，添加select列
日期：2014-05-16 浏览次数：20417 次
1.动态创建select
????? function createSelect(){
var mySelect = document.createElement("select");
????????? mySelect.id = "mySelect";
????????? document.body.appendChild(mySelect);
????? }
2.添加选项option
???? function addOption(){
????????? //根据id查找对象，
?????????? var obj=document.getElementById('mySelect');
?????????? //添加一个选项
obj.add(new Option("文本","值"));??? //这个只能在IE中有效
???????? obj.options.add(new Option("text","value")); //这个兼容IE与firefox
???? }
3.删除所有选项option
???? function removeAll(){
?????????? var obj=document.getElementById('mySelect');
obj.options.length=0;
???? }
4.删除一个选项option
function removeOne(){
?????????? var obj=document.getElementById('mySelect');
?????????? //index,要删除选项的序号，这里取当前选中选项的序号
var index=obj.selectedIndex;
obj.options.remove(index);
???? }
5.获得选项option的值
var obj=document.getElementById('mySelect');
var index=obj.selectedIndex; //序号，取当前选中选项的序号
var val = obj.options[index].value;
6.获得选项option的文本
var obj=document.getElementById('mySelect');
var index=obj.selectedIndex; //序号，取当前选中选项的序号
var val = obj.options[index].text;
7.修改选项option
var obj=document.getElementById('mySelect');
var index=obj.selectedIndex; //序号，取当前选中选项的序号
var val = obj.options[index]=new Option("新文本","新值");
8.删除select
????? function removeSelect(){
??????????? var mySelect = document.getElementById("mySelect");
mySelect.parentNode.removeChild(mySelect);
???? }
9.设置selected
obj.options[1].selected=true
整个实例的完整代码如下：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//ZH-CN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
?? <meta http-equiv="Content-Type" content="text/html">
<head>
?? <script language=JavaScript>
??? function $(id)
??? {
???? return document.getElementById(id)
??? }
??? function show()
??? {
???? var selectObj=$("area")
???? var myOption=document.createElement("option")
???? myOption.setAttribute("value","10")
???? myOption.appendChild(document.createTextNode("上海"))
???? var myOption1=document.createElement("option")
???? myOption1.setAttribute("value","100")
???? myOption1.appendChild(document.createTextNode("南京"))
???? selectObj.appendChild(myOption)
???? selectObj.appendChild(myOption1)
??? }
??? function choice()
??? {
???? var index=$("area").selectedIndex;
???? var val=$("area").options[index].getAttribute("value")
???? if(val==10)
???? {
????? var i=$("context").childNodes.length-1;
???? var remobj=$("context").childNodes[i];
???? remobj.removeNode(true)
????? var sh=document.createElement("select")
????? sh.add(new Option("浦东新区","101"))
????? sh.add(new Option("黄浦区","102"))
????? sh.add(new Option("徐汇区","103"))
????? sh.add(new Option("普陀区","104"))
????? $("context").appendChild(sh)
???? }
???? if(val==100)
???? {
????? var i=$("context").childNodes.length-1;
???? var remobj=$("context").childNodes[
