@Url.ActionLink 和 @Url.Action

问题：本人想在actionlink中，把"继续学习"，换成一张图片来显示，结果发现都一直是字符串来处理，mvc没有帮我们做这个事。 

@Html.ActionLink("继续学习", "Learning", "Item", "http", strHostNameKaoji, "", new { itemID = item.ItemID, resourceID = item.LastStudyUserResID },
    new { })

解决方法：

  第一种：要么自己重写下ActionLink做下处理

  public static MvcHtmlString ActionLinkWithImage(this HtmlHelper html, string imgSrc, string img_className, string img_width, string img_height, 

                 string actionName, string controllerName, System.Web.Routing.RouteValueDictionary routeValues, string protocolName, string hostname)
        {
            var urlHelper = new UrlHelper(html.ViewContext.RequestContext);

            string imgUrl = urlHelper.Content(imgSrc);
            TagBuilder imgTagBuilder = new TagBuilder("img");
            imgTagBuilder.MergeAttribute("src", imgUrl);
            imgTagBuilder.MergeAttribute("class", img_className);
            imgTagBuilder.MergeAttribute("width", img_width);
            imgTagBuilder.MergeAttribute("height", img_height);

            string img = imgTagBuilder.ToString(TagRenderMode.SelfClosing);

            string url = urlHelper.Action(actionName, controllerName, routeValues, protocolName, hostname);

            TagBuilder tagBuilder = new TagBuilder("a") {   InnerHtml = img };

            tagBuilder.MergeAttribute("href", url);
            return new MvcHtmlString(tagBuilder.ToString(TagRenderMode.Normal));
        }

   @Html.ActionLinkWithImage(item.Res_Item.Img.ToCDN(), "", "63", "63", "Info", "Item", new RouteValueDictionary(querystringDic), "http", strHostNameKaoji)

  第二种：还是老老实实改成Url.Action

@{  var parsed = HttpUtility.ParseQueryString("itemID = "+item.ItemID+"&&resourceID = "+item.LastStudyUserResID);
         Dictionary<string, object> querystringDic = parsed.AllKeys.ToDictionary(k => k, k => (object)parsed[k]);}

   <a href="@Url.Action("Learning", "Item", new RouteValueDictionary(querystringDic), "http", strHostNameKaoji)">
             <img width="63" height="63" src="@(item.Res_Item.Img.ToCDN())" />
       </a>