<html>
<head>
<title>Select Op</title>
<meta http-equiv="Content-Type" content="text/html;charset=gb2312" />
<script type="text/javascript">
var o;
function MoveTo(index)
{
if (index!=undefined)
{
o=source.options[index];
distinct.options.add(new Option(o.text,o.value));
source.remove(index);
}
else
{
for(var i=0;i<source.options.length;)//不要在这里控制i的增长，因为有可能删除了option
{
if(source.options[i].selected)
{
o=source.options[i];
distinct.options.add(new Option(o.text,o.value));
source.options.remove(i);
i=0;
}
else
i++;
}
}
}
function MoveBack(index)
{
if (index!=undefined)
{
o=distinct.options[index];
source.options.add(new Option(o.text,o.value));
distinct.remove(index);
}
else
{
for(var i=0;i<distinct.options.length;)//不要在这里控制i的增长，因为有可能删除了option
{
if(distinct.options[i].selected)
{
o=distinct.options[i];
source.options.add(new Option(o.text,o.value));
distinct.options.remove(i);
i=0;
}
else
i++;
}
}
}
</script>
</head>
<body>
<table width='500' border='1' cellpadding='0' cellspacing='0'>
<tr>
<td width='45%' align="center"><select id='source' multiple="multiple" style="width:200; height:300" ondblclick="MoveTo(this.selectedIndex)">
<option value='1'>Item1</option>
<option value='2'>Item2</option>
<option value='3'>Item3</option>
<option value='4'>Item4</option>
<option value='5'>Item5</option>
<option value='6'>Item6</option>
</select></td>
<td width='10%' align="center"><input type="button" value=">>" onclick="MoveTo()" /><br /><input type="button" value="<<" onclick="MoveBack()" /></td>
<td width='45%'><select id='distinct' ondblclick="MoveBack(this.selectedIndex)" style="width:200; height:300" multiple="multiple" align="center"></select></td>
</tr>
</table>
</body>
</html>
