js 操作select和option(转载)
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);
}
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[i];
remobj.removeNode(true)
var nj=document.createElement("select")
nj.add(new
Option("玄武区","201"))
nj.add(new Option("白下区","202"))
nj.add(new Option("下关区","203"))
nj.add(new
Option("栖霞区","204"))
$("context").appendChild(nj)
}
}
function calc()
{
var
x=$("context").childNodes.length-1;
alert(x)
}
function
remove()
{
var i=$("context").childNodes.length-1;
var
remobj=$("context").childNodes[i];
remobj.removeNode(true)
}
</script>
<body>
<div id="context">
<select id="area" onchange="choice()">
</select>
</div>
<input type=button value="显示"
onclick="show()">
<input type=button value="计算结点"
onclick="calc()">
<input type=button value="删除"
onclick="remove()">
</body>
</html>
改进版：在select中添加、修改、删除option元素
function watch_ini(){ // 初始
for(var i=0; i<arguments.length;
i++){
var word = document.createElement("OPTION");
word.text =
arguments[i];
watch.keywords.add(word); // watch. is form
name
}
}
function watch_add(f){ // 增加
var word =
document.createElement("OPTION");
word.text =
f.word.value;
f.keywords.add(word);
}
但上述 add()
方法只在IE下有效，为兼容FF和Opera，对上述代码进行了一下改进，改动后代码如下： function watch_ini(){ //
初始
for(var i=0; i<arguments.length; i++){
var oOption=new
Option(arguments[i],arguments[i]);
document.getElementById("MySelect")[i]=oOption;
}
}
function
watch_add(f){ // 增加
var oOption=new
Option(f.word.value,f.word.value);
f.keywords[f.keywords.length]=oOption;
}
整个实例的完整代码如下：
<!doctype html public "-//w3c//dtd html 4.0
transitional//en">
<html>
<head>
<title>javascript
select options text value</title>
<meta name="keywords"
content="javascript select options text value add modify delete
set">
<meta name="description" content="javascript select options text
value add modify delete set">
<script
language="javascript">
<!--
function watch_ini(){ // 初始
for(var
i=0; i<arguments.length; i++){
var oOption=new
Option(arguments[i],arguments[i]);
document.getElementById("MySelect")[i]=oOption;
}
}
function
watch_add(f){ // 增加
var oOption=new
Option(f.word.value,f.word.value);
f.keywords[f.keywords.length]=oOption;
}
function watch_sel(f){ //
编辑
f.word.value = f.keywords[f.keywords.selectedIndex].text;
}
function
watch_mod(f){ // 修改
f.keywords[f.keywords.selectedIndex].text =
f.word.value;
}
function watch_del(f){ //
删除
f.keywords.remove(f.keywords.selectedIndex);
}
function
watch_set(f){ // 保存
var set = "";
for(var i=0; i<f.keywords.length;
i++){
set += f.keywords[i].text +
";";
}
confirm(set);
}
//-->
</script>
</head>
<body>
<form
name="watch" method="post" action="">
<select id="MySelect"
name="keywords" size="10"
onchange="watch_sel(this.form)"></select><br>
<script
language="javascript">
<!--
watch_ini("我","你","妳","他","她","它","尔");
// 初始关键词
//-->
</script>
<input type="text" name="word"
/><br />
<input type="button" value="增加"
onclick="watch_add(this.form);" />
<input type="button" value="修改"
onclick="watch_mod(this.form);" />
<input type="button" value="删除"
onclick="watch_del(this.form);" />
<input type="button" value="保存"
onclick="watch_set(this.form);" />
</form>
用一个字符串创建一个数组方法:
<script language="javascript">
- </body>
</html> - <script>
- function spli(){
- datastr="2,2,3,5,6,6";
- var str= new Array();
- str=datastr.split(",");
- for (i=0;i<str.length ;i++ )
- { document.write(str[i]+"<br/>"); }
- }
- spli();
- </script
