如何循環遍歷所有路線？

Question

從mvc（2）用戶控件中，我想遍歷所有路由值。

所以，如果我有這樣的控制器：

UserController 
AccountController 

我所需要的值的集合，它會出現在類似的網址：

/user/... 
/account/... 

即值用戶帳戶。

我怎樣才能得到這個？

我試過RouteTables，但無法弄清楚。

Answer 1

哦，真的是一個很好的問題，讓我的自我忙一小時。 爲了實現所需的功能，我們需要掛接到MVC源代碼和一點點反射。

1. 缺省路由的名稱不可用，所以我們需要寫一個路由集合擴展名來保存路由名稱中的RouteData令牌。

   public static Route MapRouteWithName(this RouteCollection routes,string name, string url, object defaults=null, object constraints=null) 
   { 
   
   Route route = routes.MapRoute(name, url, defaults, constraints); 
   route.DataTokens = new RouteValueDictionary(); 
   route.DataTokens.Add("RouteName", name); 
   return route; 
   } 
   

2. 修改在Global.asax圖路線要進行的調用以前的擴展

   routes.MapRouteWithName(
         "Default", // Route name 
         "{controller}/{action}/{id}", // URL with parameters 
         new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults 
        ); 
   

3. 修改了MVC PathHelper一點點。（包含此幫手項目）

   using System; 
   using System.Collections.Specialized; 
   using System.Web; 
   
   public static class PathHelpers 
   { 
   
   // this method can accept an app-relative path or an absolute path for contentPath 
   public static string GenerateClientUrl(HttpContextBase httpContext, string contentPath) 
   { 
       if (String.IsNullOrEmpty(contentPath)) 
       { 
        return contentPath; 
       } 
   
       // many of the methods we call internally can't handle query strings properly, so just strip it out for 
       // the time being 
       string query; 
       contentPath = StripQuery(contentPath, out query); 
   
       return GenerateClientUrlInternal(httpContext, contentPath) + query; 
   } 
   
   private static string GenerateClientUrlInternal(HttpContextBase httpContext, string contentPath) 
   { 
       if (String.IsNullOrEmpty(contentPath)) 
       { 
        return contentPath; 
       } 
   
       // can't call VirtualPathUtility.IsAppRelative since it throws on some inputs 
       bool isAppRelative = contentPath[0] == '~'; 
       if (isAppRelative) 
       { 
        string absoluteContentPath = VirtualPathUtility.ToAbsolute(contentPath, httpContext.Request.ApplicationPath); 
        string modifiedAbsoluteContentPath = httpContext.Response.ApplyAppPathModifier(absoluteContentPath); 
        return GenerateClientUrlInternal(httpContext, modifiedAbsoluteContentPath); 
       } 
   
       string relativeUrlToDestination = MakeRelative(httpContext.Request.Path, contentPath); 
       string absoluteUrlToDestination = MakeAbsolute(httpContext.Request.RawUrl, relativeUrlToDestination); 
       return absoluteUrlToDestination; 
   } 
   
   public static string MakeAbsolute(string basePath, string relativePath) 
   { 
       // The Combine() method can't handle query strings on the base path, so we trim it off. 
       string query; 
       basePath = StripQuery(basePath, out query); 
       return VirtualPathUtility.Combine(basePath, relativePath); 
   } 
   
   public static string MakeRelative(string fromPath, string toPath) 
   { 
       string relativeUrl = VirtualPathUtility.MakeRelative(fromPath, toPath); 
       if (String.IsNullOrEmpty(relativeUrl) || relativeUrl[0] == '?') 
       { 
        // Sometimes VirtualPathUtility.MakeRelative() will return an empty string when it meant to return '.', 
        // but links to {empty string} are browser dependent. We replace it with an explicit path to force 
        // consistency across browsers. 
        relativeUrl = "./" + relativeUrl; 
       } 
       return relativeUrl; 
   } 
   
   private static string StripQuery(string path, out string query) 
   { 
       int queryIndex = path.IndexOf('?'); 
       if (queryIndex >= 0) 
       { 
        query = path.Substring(queryIndex); 
        return path.Substring(0, queryIndex); 
       } 
       else 
       { 
        query = null; 
        return path; 
       } 
   } 
   
   } 
   

4. 在控制器中添加少量幫手方法

   public static string GenerateUrl(string routeName, string actionName, string controllerName, RouteCollection routeCollection, RequestContext requestContext) 
   { 
   
       RouteValueDictionary mergedRouteValues = MergeRouteValues(actionName, controllerName); 
   
       VirtualPathData vpd = routeCollection.GetVirtualPathForArea(requestContext, routeName, mergedRouteValues); 
       if (vpd == null) 
       { 
        return null; 
       } 
   
       string modifiedUrl = PathHelpers.GenerateClientUrl(requestContext.HttpContext, vpd.VirtualPath); 
       return modifiedUrl; 
   } 
   public static RouteValueDictionary MergeRouteValues(string actionName, string controllerName) 
   { 
       // Create a new dictionary containing implicit and auto-generated values 
       RouteValueDictionary mergedRouteValues = new RouteValueDictionary(); 
   
       // Merge explicit parameters when not null 
       if (actionName != null) 
       { 
        mergedRouteValues["action"] = actionName; 
       } 
   
       if (controllerName != null) 
       { 
        mergedRouteValues["controller"] = controllerName; 
       } 
   
       return mergedRouteValues; 
   } 
   

5. 現在我們可以編寫一些反射邏輯來讀取控制器，動作和routenames。

   Dictionary<string, List<string>> controllersAndActions = new Dictionary<string, List<string>>(); 
   
   // Get all the controllers 
   var controllers = Assembly.GetExecutingAssembly().GetTypes().Where(t => typeof(Controller).IsAssignableFrom(t)); 
   
   foreach (var controller in controllers) 
   { 
       List<string> actions = new List<string>(); 
       //Get all methods without HttpPost and with return type action result 
       var methods = controller.GetMethods().Where(m => typeof(ActionResult).IsAssignableFrom(m.ReturnType)).Where(a=>!a.GetCustomAttributes(typeof(HttpPostAttribute),true).Any()); 
       methods.ToList().ForEach(a => { 
        actions.Add(a.Name); 
       }); 
       var controllerName = controller.Name; 
       if (controllerName.EndsWith("Controller")) 
       { 
        var nameLength = controllerName.Length - "Controller".Length; 
        controllerName = controllerName.Substring(0, nameLength); 
       } 
       controllersAndActions.Add(controllerName, actions); 
   } 
   List<string> allowedRoutes = new List<string>(); 
   
   var routeNames = RouteTable.Routes.Where(o=>o.GetRouteData(this.HttpContext)!=null).Select(r=>r.GetRouteData(this.HttpContext).DataTokens["RouteName"].ToString()); 
   foreach (var cName in controllersAndActions) 
   { 
       foreach (var aName in cName.Value) 
       { 
        foreach (var item in routeNames) 
        { 
         allowedRoutes.Add(GenerateUrl(item, aName, cName.Key, RouteTable.Routes, this.Request.RequestContext)); 
        } 
       } 
   
   } 
   

6. 要記住的要點：如果在路由已定義的任何默認參數，那麼URL爲那些控制器和操作將是空的。例如在上面的例子中 「/首頁/索引」 將顯示爲 「/」

7. 下載示例應用程序Link To Download