基于jQuery实现下拉框

        $(function(){
            $('#add').click(function(){
                var $options = $('#select1 option:selected');
                $options.appendTo("#select2");
            });
            $('#remove').click(function(){
                var $options = $('#select2 option:selected');
                $options.appendTo("#select1");
            });
            $('#add_all').click(function(){
                var $options = $('#select1 option');
                $options.appendTo("#select2");
            });
            $('#remove_all').click(function(){
                var $options = $('#select2 option');
                $options.appendTo("#select1");
            });
            $('#select1').dblclick(function(){
               var $options = $("option:selected",this); //获取选中的选项
                $options.appendTo('#select2');
            });
            $('#select2').dblclick(function(){
                var $options = $("option:selected",this); //获取选中的选项
                $options.appendTo('#select1');
            });
        });

   <div style="width: 250px">
   <div class="content" style="float: left">
       <select multiple id="select1" style="width: 100px;height: 160px;">
           <option value="1">选项1</option>
           <option value="2">选项2</option>
           <option value="3">选项3</option>
           <option value="4">选项4</option>
           <option value="5">选项5</option>
           <option value="6">选项6</option>
           <option value="7">选项7</option>
           <option value="8">选项8</option>
       </select>
       <div>
           <span id="add">选中添加到右边&gt;&gt;</span><br>
           <span id="add_all">全部添加到右边&gt;&gt;</span>
       </div>
   </div>
   <div style="float: right;">
       <select multiple id="select2" style="width: 100px;height: 160px;">
       </select>
       <div>
           <span id="remove">&lt;&lt;选中删除到左边</span><br>
           <span id="remove_all">&lt;&lt;全部删除到左边</span>
       </div>
   </div>
</div>