前面加上表单名xxx.
<html>
<head>
<script>
function addOption()
{
var the_option= new Option(xxx.select1.value,xxx.select1.value);
xxx.select2.add(the_option);
xxx.select2.selectedIndex = xxx.select2.options.length-1
}
function delOption()
{
xxx.select2.selectedIndex = xxx.select2.options.length + 1
xxx.select2.options = ""
}function delOpetion2() {
xxx.select2.options.remove(xxx.select2.selectedIndex);
}
</script>
</head>
<body>
<form name=xxx method=post action="xx.asp">
<select name=select1 multiple>
<option value='aaaaa'>aaaaa</option>
<option value='bbbbb'>bbbbb</option>
<option value='ccccc'>ccccc</option>
<option value='ddddd'>ddddd</option>
<option value='eeeee'>eeeee</option>
</select>
<input type=button value="==>" onclick="addOption()">
<input type=button value="<==" onclick="delOpetion2()">
<select name=select2 multiple></select>
</form>
</body>
</html>
<html>
<head>
<script>
function addOption()
{
var the_option= new Option(xxx.select1.value,xxx.select1.value);
xxx.select2.add(the_option);
xxx.select2.selectedIndex = xxx.select2.options.length-1
}
function delOption()
{
xxx.select2.selectedIndex = xxx.select2.options.length + 1
xxx.select2.options = ""
}function delOpetion2() {
xxx.select2.options.remove(xxx.select2.selectedIndex);
}
</script>
</head>
<body>
<form name=xxx method=post action="xx.asp">
<select name=select1 multiple>
<option value='aaaaa'>aaaaa</option>
<option value='bbbbb'>bbbbb</option>
<option value='ccccc'>ccccc</option>
<option value='ddddd'>ddddd</option>
<option value='eeeee'>eeeee</option>
</select>
<input type=button value="==>" onclick="addOption()">
<input type=button value="<==" onclick="delOpetion2()">
<select name=select2 multiple></select>
</form>
</body>
</html>
<head>
<script>
function addOption()
{
var the_option= new Option(select1.value,select1.value);
select2.add(the_option);
select2.selectedIndex = select2.options.length-1
}
function delOption()
{
select2.selectedIndex = select2.options.length + 1
select2.options = ""
}function delOpetion2() {
try{
select2.options.remove(select2.selectedIndex);
}
catch(x){alert('请先选择再删除')}
}
</script>
</head>
<body>
<select name=select1 multiple>
<option value='aaaaa'>aaaaa</option>
<option value='bbbbb'>bbbbb</option>
<option value='ccccc'>ccccc</option>
<option value='ddddd'>ddddd</option>
<option value='eeeee'>eeeee</option>
</select>
<input type=button value="==>" onclick="addOption()">
<input type=button value="<==" onclick="delOpetion2()">
<select name=select2 multiple></select>
</body>
</html>
<head>
<script>
function addOption()
{
var the_option= new Option(select1.value,select1.value);
select2.add(the_option);
select2.selectedIndex = select2.options.length-1
}
function delOption()
{
select2.selectedIndex = select2.options.length + 1
select2.options = ""
}function delOpetion2() {
select2.options.remove(select2.selectedIndex);
}
</script>
</head>
<body>
<select name=select1 multiple>
<option value='aaaaa'>aaaaa</option>
<option value='bbbbb'>bbbbb</option>
<option value='ccccc'>ccccc</option>
<option value='ddddd'>ddddd</option>
<option value='eeeee'>eeeee</option>
</select>
<input type=button value="==>" onclick="addOption()">
<input type=button value="<==" onclick="delOpetion2()">
<select name=select2 multiple></select>
</body>
</html>