如下代码: <ul class="imagebg" id="imagebg">                @{
                    foreach (Attachment u in (IList<Attachment>)ViewData["ReturnList"]) 
                    {
                        <li data-sPic='@{@u.URL}'><a href="javascript:void(0)" class="bannerbg_main" style='background:url(@{@u.URL}) 50% 50% no-repeat;' ></a></li>                      
                    }
                 }            
                    
            </ul>我要@{@u.URL}在这个读取之前加上: @Url.Content(@{@u.URL}),该怎么写?谢谢.