option内容移动

<select id="select1" style="width: 100px; height: 160px;" multiple="multiple">
<option>1</option>
<option>11</option>
<option>12</option>
<option>13</option>
<option>14</option>
</select>
<select id="select2" style="width: 100px; height: 160px;" multiple="multiple">
<option>2</option>
<option>21</option>
<option>22</option>
<option>23</option>
<option>24</option>
</select>
<button id="lbtn">左移动一个</button>
<button id="labtn">左移动全部</button>
<button id="rbtn">右移动一个</button>
<button id="rabtn">右移动全部</button>
<script type="text/javascript" src="js/jquery.min.js" ></script>
<script type="text/javascript">
$(function(){
//单个移动
$("#lbtn").bind("click",function(){
var b=$("#select1 option:selected").remove();
/*alert(b);
b.appendTo("#select2");*/
$("#select2").append(b);
});
//全部移动
$("#labtn").bind("click",function(){
var b=$("#select1 option").remove();
/*alert(b);
b.appendTo("#select2");*/
$("#select2").append(b);
});
});
</script>