selector 添加

$(document).ready(function(){      $("#listOne").dblclick(   function()   {         $("#listOne option:selected").appendTo("#listTwo");            }         );          });  

?html 内容

<select size="10" id="listOne">        <option value="ddd" />eeeee     <option value="ddd1" />eeeee1     <option value="ddd2" />eeeee2     <option value="ddd3" />eeeee3     <option value="ddd4" />eeeee4    </select> <input type="button" onclick="usb()" value="enter" /><div id="mmu"></div><select size="10" id="listTwo">   

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