从select中选择option后如何转到相应的数据页面中去的JS代码

<select onchange="selected(this)">
                <optgroup label="A">
                <option value="http://www.glambox.com/apple">Apple</option>
              </optgroup>

            

                <optgroup label="B">
              <option value="http://www.glambox.com/burberry">burberry</option>
           </optgroup>

            

                <optgroup label="C">
           <option value="http://www.glambox.com/index.php?route=product/manufacturer/info&amp;manufacturer_id=9">Canon</option>
         </optgroup>

            

              <optgroup label="D">
                    <option value="http://www.glambox.com/demo">demo</option>
              </optgroup>

            

              
  </select>

这代代码要求点击相应的连接跳转到相应的页面，js代码如下

<script> 
function selected(o){ 
location.href=o.value;
} 
</script> 

上面的select也可以这样写

<select onchange="location.href=this.value">