两个select多选模式的选项相互移动(示例代码)

如下所示：


代码如下:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<script type="text/javascript">
function copyToList(from,to){

var fromList=eval('document.forms[0].'+from);
    var toList=eval('document.forms[0].'+to);

if(toList.options.length > 0 && toList.options[0].value == 'temp'){
            toList.options.length=0;
    }

var sel=false;

for(i = 0;i < fromList.options.length;i++){
        var current=fromList.options[i];
        if(current.selected){
            sel=true;
            if(current.value=='temp'){
                alert('不能选择这个项目!');
                return;
            }
            txt=current.text;
            val=current.value;
            toList.options[toList.length]=new Option(txt,val);
            fromList.options[i]=null;
            i--;
        }
    }

if(!sel) alert('你还没有选择任何项目!');
}

function allSelect(){   
    var chsen=document.getElementById('chosen');
    //如果chsen列表框为0或第一个选项值为'temp'
    if(chsen.length && chsen.options[0].value=="temp")
        return;

for(var i=0;i<chsen.length;i++){
            chsen.options[i].selected=true;
    }

//得到数据
 function getdata() {
            var List = document.forms[0].RoleList;
　　　　　　　//得到一个隐藏文本框对象
            var roles = document.getElementById("TRoleList");
            roles.value = "";
            var s = "";
            if (List.length != 0) {
                for (i = 0; i < List.length; i++) {
                    s += List.options[i].value + ",";
                }
            }

roles.value = s;
        }
}
</script>
</head>
<body>
<table border="0">
<form onSubmit="allSelect()">  
<tr>  
<td>  
<select name="possible" size="4" MULTIPLE width="200" style="width:200px">  
<option value="1">中国广州</option>
<option value="2">中国上海</option>
<option value="3">中国北京</option>  
<option value="4">中国武汉</option>
</select>  
</td>  
<td><a href="javascript:copyToList('possible','chosen')">添加至右方--><br>  
<br>
</a><a href="javascript:copyToList('chosen','possible')"><--添加至左方</a></td>  
<td>  
<select name="chosen"   size="4" MULTIPLE  width="200"  style="width:200px;">  
<option value="temp">从左边选择你的地区</option>
</select>  
</td>  
</tr>
</form>  
</table>
<input type="button"  value="提交"  onclick="allSelect()" />yle
<input type="text" style="display:none;" id="TRoleList">
</body>
</html>