ASP.NET MVC 3：有没有办法从控制器的类型中获取控制器的字符串名称？

Question

使用 MVC3 中的 UrlHelper，您可以使用字符串为控制器和操作构建 URL：

@Url.Action("Index", "Somewhere")

这会将请求路由到SomewhereController.Index()。

我想做的是获取控制器和操作的 URL，但传递控制器的类型：

@Url.Action("Index", typeof(SomewhereController))

有没有办法做到这一点？

---

编辑/澄清：

我意识到控制器的约定是控制器名称路由到名为 {Name}Controller 的类，因此我可以从 Type.Name 的末尾删除“控制器”。我想我假设有一种方法可以通过一些自定义路由来覆盖这个约定。虽然我看的越多，我不确定这是否可能......

也许 MVC3 只能 路由到名为“*Controller”的类？我正在梳理 MVC3 源代码，寻找硬编码的“控制器”某处，但还没有找到答案……但如果可以将“某处”路由到类SomewhereFoo 而不是SomewhereController，那么仅仅从类名中删除“Controller”是不正确的。

如果有人可以为我提供证据支持或反对“控制器”在某处被硬编码到 MVC3 中，那么我会对“只需从名称中删除控制器”方法感到更自在。

Answer 1

目前尚无此扩展，但您可以编写自己的扩展，以 MvcFutures 的 ActionLink 为模型。我建议使用像@Url.Action<SomewhereController>( c => c.Index )这样的通用方法

public static UrlHelperExtensions
{
    public static string Action<TController>( this UrlHelper helper,  Expression<Action<T>> action ) where TController : Controller
    {
        var routeValues = GetRouteValuesFromExpression( action ); 
        return helper.Action( routeValues["action"], routeValues );
    }

    // copied from MvcFutures
    // http://aspnet.codeplex.com/SourceControl/changeset/view/72551#266392
    private static RouteValueDictionary GetRouteValuesFromExpression<TController>(Expression<Action<TController>> action) where TController : Controller
    {
        if (action == null) {
            throw new ArgumentNullException("action");
        }

        MethodCallExpression call = action.Body as MethodCallExpression;
        if (call == null) {
            throw new ArgumentException(MvcResources.ExpressionHelper_MustBeMethodCall, "action");
        }

        string controllerName = typeof(TController).Name;
        if (!controllerName.EndsWith("Controller", StringComparison.OrdinalIgnoreCase)) {
            throw new ArgumentException(MvcResources.ExpressionHelper_TargetMustEndInController, "action");
        }
        controllerName = controllerName.Substring(0, controllerName.Length - "Controller".Length);
        if (controllerName.Length == 0) {
            throw new ArgumentException(MvcResources.ExpressionHelper_CannotRouteToController, "action");
        }

        // TODO: How do we know that this method is even web callable?
        //      For now, we just let the call itself throw an exception.

        var rvd = new RouteValueDictionary();
        rvd.Add("Controller", controllerName);
        rvd.Add("Action", call.Method.Name);
        AddParameterValuesFromExpressionToDictionary(rvd, call);
        return rvd;
    }
}

Answer 2

@Url.Action("Index", typeof(SomewhereController).Name.Replace("Controller", ""))

Answer 3

有多种方法可以做到这一点。如果您使用的是类型，我能想到的最简单的方法是实现 Name 属性，如下所示：

public static string Name { get { return "Somewhere"; } }

然后像这样调用你的 Action：

@Url.Action("Index", SomewhereController.Name);

Answer 4

你可以创建一个 Razor 助手：

@helper MyAction(string action, Type controller) {
    var controllerName = typeof(controller)
        .Name.Replace("Controller", "");
    @Url.Action(action, controllerName);
}

然后可以用来代替@Url.Action:

@MyAction("ActionName", typeof(MyController))

Answer 5

基于accepted answer:

用法

var url = Url.RouteUrl<MyController>(c => c.MyAction(dummy,args));

或：

@using (Html.BeginForm(Url.Route<MyController>(c => c.MyAction(dummy,args))))
{
    // yadda yadda
}

扩展方法

public static class ActionRouteHelper
{
    /// <summary>
    /// Given a controller/action selector, return its URL route
    /// </summary>
    /// <typeparam name="TController"></typeparam>
    /// <param name="url">helper extended</param>
    /// <param name="action">A lambda for choosing an action from the indicated controller.  May need to provide dummy method arguments.</param>
    /// <returns></returns>
    public static string RouteUrl<TController>(this UrlHelper url, Expression<Action<TController>> action) where TController : Controller
    {
        return url.RouteUrl(url.Route(action));
    }
    /// <summary>
    /// Given a controller/action selector, return its URL route
    /// </summary>
    /// <remarks>See inspiration from https://stackoverflow.com/a/8252301/1037948 </remarks>
    /// <typeparam name="TController">the controller class</typeparam>
    /// <param name="url">helper extended</param>
    /// <param name="action">A lambda for choosing an action from the indicated controller.  May need to provide dummy method arguments.</param>
    /// <returns></returns>
    public static RouteValueDictionary Route<TController>(this UrlHelper url, Expression<Action<TController>> action) where TController : Controller
    {
        // TODO: validate controller name for suffix, non-empty result, if that's important to you here rather than the link just not working
        var controllerName = typeof(TController).Name.Replace("Controller", string.Empty);

        // strip method name out of the expression, the lazy way (https://stackoverflow.com/questions/671968/retrieving-property-name-from-lambda-expression/17220748#17220748)
        var actionName = action.ToString(); // results in something like "c => c.MyAction(arg1,arg2)"
        var startOfMethodName = actionName.IndexOf('.')+1;
        var startOfArgList = actionName.IndexOf('(');
        actionName = actionName.Substring(startOfMethodName, startOfArgList - startOfMethodName);

        return new RouteValueDictionary {
            { "Controller", controllerName },
            { "Action", actionName }
        };
    }
}