Question

所以这就是：

我有一个html帮助器，它使用当前url的可选参数呈现ActionLink s。这个html帮助器还允许您根据需要添加更多可选参数，并将它们合并为1 RouteValueDictionary。

    public static string ActionLinkwParams(this HtmlHelper helper, string linktext, string action, string controller, object extraRVs, object htmlAttributes) {

        //get current optional params from current URL
        NameValueCollection c = helper.ViewContext.RequestContext.HttpContext.Request.QueryString;

        //put those in a dict
        RouteValueDictionary r = new RouteValueDictionary();
        foreach (string s in c.AllKeys) {
            r.Add(s, c[s]);
        }

        RouteValueDictionary htmlAtts = new RouteValueDictionary(htmlAttributes);

        RouteValueDictionary extra = new RouteValueDictionary(extraRVs);

        //merge them
        RouteValueDictionary m = RouteValues.MergeRouteValues(r, extra);

        return helper.ActionLink(linktext, action, controller, m, htmlAtts).ToHtmlString();
    }

这很完美，但我现在添加了SecurityAware Actionlinks。

所以

        return helper.ActionLink(linktext, action, controller, m, htmlAtts).ToHtmlString();

成为

        return helper.SecurityTrimmedActionLink(linktext, action, controller, m, htmlAtts);

然后调用：

   public static string SecurityTrimmedActionLink(this HtmlHelper htmlHelper, string linkText, string action, string controller, object extraRVs, object htmlAttributes) {
        return SecurityTrimmedActionLink(htmlHelper, linkText, action, controller, extraRVs, htmlAttributes, false);
    }

    public static string SecurityTrimmedActionLink(this HtmlHelper htmlHelper, string linkText, string action, string controller, object extraRVs, object htmlAttributes, bool showDisabled) {
        if (controller == null) {
            RouteData routeData = htmlHelper.ViewContext.RouteData;
            controller = routeData.GetRequiredString("controller");
        }
        if (IsAccessibleToUser(action, controller)) {
            return htmlHelper.ActionLink(linkText, action, controller, extraRVs, htmlAttributes).ToHtmlString();
        } else {
            return showDisabled ? String.Format("<span>{0}</span>", linkText) : "";
        }
    }

现在这不起作用。它编译，但我的URL看起来不太好。

   <a count="3" keys="System.Collections.Generic.Dictionary`2+KeyCollection[System.String,System.Object]" values="System.Collections.Generic.Dictionary`2+ValueCollection[System.String,System.Object]" href="/2011-2012/Instelling?Count=3&amp;Keys=System.Collections.Generic.Dictionary%602%2BKeyCollection%5BSystem.String%2CSystem.Object%5D&amp;Values=System.Collections.Generic.Dictionary%602%2BValueCollection%5BSystem.String%2CSystem.Object%5D">Back to List</a>

正如你所看到的，之前的工作，现在并不是因为它将RouteValueDictionary作为对象，这给了我不想要的结果。

所以我想，如果我再次让他们RouteValueDictionary怎么办？

       if (IsAccessibleToUser(action, controller)) {

            RouteValueDictionary parsedextraRVs = null;
            if (extraRVs != null && extraRVs.GetType().Name == "RouteValueDictionary") {
                parsedextraRVs = (RouteValueDictionary)extraRVs;
            }

            RouteValueDictionary parsedHtmlAttributes = null;
            if (htmlAttributes != null && htmlAttributes.GetType().Name == "RouteValueDictionary") {
                parsedHtmlAttributes = (RouteValueDictionary)htmlAttributes;
            }


            return htmlHelper.ActionLink(linkText, action, controller, parsedextraRVs == null ? extraRVs : parsedextraRVs, parsedHtmlAttributes == null ? htmlAttributes : parsedHtmlAttributes).ToHtmlString();
        }

但这也给了我刚刚发布的网址。为什么这在我的ActionLinkwParams方法中有效，而在ActionLinkwParams调用SecurityTrimmedActionLink方法时却没有？以及如何解决此问题？

Answer 1

将SecurityTrimmedActionLink方法的签名修改为：

public static string SecurityTrimmedActionLink(
    this HtmlHelper htmlHelper, 
    string linkText, 
    string action, 
    string controller, 
    RouteValueDictionary extraRVs, 
    RouteValueDictionary htmlAttributes
)

请注意this和this之间的区别。在你的情况下（那个不起作用的那个）你正在调用第二个重载的对象，但在你的情况下，你没有传递匿名对象，而是一个RouteValueDictionary，它被视为一个匿名对象及其公共属性（Count，键，值）被序列化为属性。

备注：您的助手方法不正确。他们返回字符串。这不是它应该如何。帮助方法应该返回MvcHtmlString。

所以而不是

public static string ActionLinkwParams(...)
{
    ...
    return helper.ActionLink(linktext, action, controller, m, htmlAtts).ToHtmlString();
}

它应该是：

public static MvcHtmlString ActionLinkwParams(...)
{
    ...
    return helper.ActionLink(linktext, action, controller, m, htmlAtts);
}

Answer 2

所以我最后做了什么（感谢Darin）做了一些额外的重载来完成这项工作。

    public static MvcHtmlString SecurityTrimmedActionLink(this HtmlHelper htmlHelper, string linkText, string action) {
        return SecurityTrimmedActionLink(htmlHelper, linkText, action, null, null);
    }

    public static MvcHtmlString SecurityTrimmedActionLink(this HtmlHelper htmlHelper, string linkText, string action, string controller) {
        return SecurityTrimmedActionLink(htmlHelper, linkText, action, controller, null);
    }

    public static MvcHtmlString SecurityTrimmedActionLink(this HtmlHelper htmlHelper, string linkText, string action, object extraRVs) {
        return SecurityTrimmedActionLink(htmlHelper, linkText, action, null, extraRVs, null);
    }

    public static MvcHtmlString SecurityTrimmedActionLink(this HtmlHelper htmlHelper, string linkText, string action, string controller, object extraRVs) {
        return SecurityTrimmedActionLink(htmlHelper, linkText, action, controller, extraRVs, null);
    }

    public static MvcHtmlString SecurityTrimmedActionLink(this HtmlHelper htmlHelper, string linkText, string action, RouteValueDictionary extraRVs) {
        return SecurityTrimmedActionLink(htmlHelper, linkText, action, null, extraRVs, null);
    }

    public static MvcHtmlString SecurityTrimmedActionLink(this HtmlHelper htmlHelper, string linkText, string action, string controller, RouteValueDictionary extraRVs) {
        return SecurityTrimmedActionLink(htmlHelper, linkText, action, controller, extraRVs, null);
    }

    public static MvcHtmlString SecurityTrimmedActionLink(this HtmlHelper htmlHelper, string linkText, string action, string controller, object extraRVs, object htmlAttributes) {

        RouteValueDictionary rv = new RouteValueDictionary(extraRVs);
        RouteValueDictionary html = new RouteValueDictionary(htmlAttributes);

        return SecurityTrimmedActionLink(htmlHelper, linkText, action, controller, extraRVs, html);
    }

    public static MvcHtmlString SecurityTrimmedActionLink(this HtmlHelper htmlHelper, string linkText, string action, string controller, RouteValueDictionary extraRVs, IDictionary<String, Object> htmlAttributes) {
        if (controller == null) {
            RouteData routeData = htmlHelper.ViewContext.RouteData;
            controller = routeData.GetRequiredString("controller");
        }
        if (IsAccessibleToUser(action, controller)) {
            return htmlHelper.ActionLink(linkText, action, controller, extraRVs, htmlAttributes);
        } else {
            return MvcHtmlString.Empty;
        }
    }

mvc ActionLink中的RouteValueDictionary / object问题

2 个答案: