从 Razor 声明式视图使用 MVC HtmlHelper 扩展 [英] Using MVC HtmlHelper extensions from Razor declarative views

问题描述

我试图在我的 App_Code 文件夹中为 MVC 3 RTM 项目创建一个 Razor 声明性助手.

I was trying to create a Razor declarative helper in my App_Code folder for an MVC 3 RTM project.

我遇到的问题是 MVC HtmlHelper 扩展(如 ActionLink)不可用.这是因为编译的帮助程序派生自 System.Web.WebPages.HelperPage，虽然它公开了一个 Html 属性，但它的类型是 System.Web.WebPages.HtmlHelper 而不是 System.Web.Mvc.HtmlHelper.

The problem I ran into was that the MVC HtmlHelper extensions, like ActionLink, aren't available. This is because the compiled helpers derive from System.Web.WebPages.HelperPage, and though it exposes an Html property, its of type System.Web.WebPages.HtmlHelper rather than System.Web.Mvc.HtmlHelper.

我遇到的错误类型的一个例子是:

An example of the kind of error I was getting is:

'System.Web.Mvc.HtmlHelper' 没有包含ActionLink"的定义并且没有扩展方法ActionLink"接受类型的第一个参数'System.Web.Mvc.HtmlHelper' 可以是找到了(您是否缺少使用指令或程序集引用?)

'System.Web.Mvc.HtmlHelper' does not contain a definition for 'ActionLink' and no extension method 'ActionLink' accepting a first argument of type 'System.Web.Mvc.HtmlHelper' could be found (are you missing a using directive or an assembly reference?)

我唯一的解决方案是创建我自己的 HelperPage 并覆盖 Html 属性:

My only solution has been to create my own HelperPage and override the Html property:

using System.Web.WebPages;

public class HelperPage : System.Web.WebPages.HelperPage 
{
    // Workaround - exposes the MVC HtmlHelper instead of the normal helper
    public static new HtmlHelper Html
    {
        get { return ((System.Web.Mvc.WebViewPage) WebPageContext.Current.Page).Html; }
    }
}

然后我必须在每个助手的顶部写下以下内容:

I then have to write the following at the top of every helper:

@inherits FunnelWeb.Web.App_Code.HelperPage
@using System.Web.Mvc
@using System.Web.Mvc.Html

@helper DoSomething()
{
    @Html.ActionLink("Index", "Home")
}

在 MVC 3 中是不是要这么难，还是我做错了什么?

Is it meant to be this hard in MVC 3, or am I doing something wrong?

推荐答案

看一看 Marcind 对这个问题的回答.您遇到的是将声明性视图放在 App_Code 文件夹中的限制.

Take a look at Marcind's answer to this question. What you're experiencing is a limitation of putting declarative views in the App_Code folder.

将你的助手放在 App_Code 中是有效的但有一定的局限性影响某些 MVC 场景(对于示例:无法访问标准 MVChtml.帮手)

Putting your helpers in App_Code works but has certain limitations that impact certain MVC scenarios (for example: no access to standard MVC Html. helpers)

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