如何在ASP.NET MVC中更改默认视图位置方案？

我想根据当前UI区域性在运行时更改视图位置。如何使用默认的Web表单视图引擎实现这一点

基本上，我想知道如何使用

WebFormViewEngine

实现所包含的内容

是否有其他视图引擎可以让我在运行时控制视图位置

---

---

编辑：我的URL应该如下所示

{lang}/{controller}/{action}/{id}

。我不需要依赖于语言的控制器和视图，它们是使用资源本地化的。然而，在某些语言中，很少有不同的观点。因此，我需要告诉视图引擎首先查看特定于语言的文件夹。

我认为解决方案是创建您自己的视图引擎，它继承了WebFormViewEngine。在构造函数中，它应该从当前线程检查当前UI区域性，并添加适当的位置。只是别忘了将其添加到视图引擎中

这应该是这样的：

public class ViewEngine : WebFormViewEngine
{
    public ViewEngine()
    {
        if (CultureIsX())
            ViewLocationFormats = new string[]{"route1/controller.aspx"};
        if (CultureIsY())
            ViewLocationFormats = new string[]{"route2/controller.aspx"};
    }
}

在global.asax中：

ViewEngines.Engines.Add(new ViewEngine());

---

必须更改VirtualPathProviderViewEngine.GetPathFromGeneralName以允许路由中的附加参数。它不是公共的，这就是为什么您必须将

GetPath

，

GetPathFromGeneralName

，

IsSpecificPath

…复制到您自己的

ViewEngine

实现中

你说得对：这看起来像是一次彻底的重写。我希望

GetPathFromGeneralName

是公共的

using System.Web.Mvc;
using System;
using System.Web.Hosting;
using System.Globalization;
using System.Linq;

namespace MvcLocalization
{
    public class LocalizationWebFormViewEngine : WebFormViewEngine
    {
        private const string _cacheKeyFormat = ":ViewCacheEntry:{0}:{1}:{2}:{3}:";
        private const string _cacheKeyPrefix_Master = "Master";
        private const string _cacheKeyPrefix_Partial = "Partial";
        private const string _cacheKeyPrefix_View = "View";
        private static readonly string[] _emptyLocations = new string[0];

        public LocalizationWebFormViewEngine()
        {
            base.ViewLocationFormats = new string[] { 
                    "~/Views/{1}/{2}/{0}.aspx", 
                    "~/Views/{1}/{2}/{0}.ascx", 
                    "~/Views/Shared/{2}/{0}.aspx", 
                    "~/Views/Shared/{2}/{0}.ascx" ,
                     "~/Views/{1}/{0}.aspx", 
                    "~/Views/{1}/{0}.ascx", 
                    "~/Views/Shared/{0}.aspx", 
                    "~/Views/Shared/{0}.ascx" 

            };

        }

        private VirtualPathProvider _vpp;

        public override ViewEngineResult FindView(ControllerContext controllerContext, string viewName, string masterName, bool useCache)
        {
            if (controllerContext == null)
                throw new ArgumentNullException("controllerContext");

            if (String.IsNullOrEmpty(viewName))
                throw new ArgumentException( "viewName");

            string[] viewLocationsSearched;
            string[] masterLocationsSearched;

            string controllerName = controllerContext.RouteData.GetRequiredString("controller");
            string viewPath = GetPath(controllerContext, ViewLocationFormats, "ViewLocationFormats", viewName, controllerName, _cacheKeyPrefix_View, useCache, out viewLocationsSearched);
            string masterPath = GetPath(controllerContext, MasterLocationFormats, "MasterLocationFormats", masterName, controllerName, _cacheKeyPrefix_Master, useCache, out masterLocationsSearched);

            if (String.IsNullOrEmpty(viewPath) || (String.IsNullOrEmpty(masterPath) && !String.IsNullOrEmpty(masterName)))
            {
                 return new ViewEngineResult(viewLocationsSearched.Union(masterLocationsSearched));
            }

            return new ViewEngineResult(CreateView(controllerContext, viewPath, masterPath), this);
        }

        private string GetPath(ControllerContext controllerContext, string[] locations, string locationsPropertyName, string name, string controllerName, string cacheKeyPrefix, bool useCache, out string[] searchedLocations)
        {
            searchedLocations = _emptyLocations;

            if (String.IsNullOrEmpty(name))
                return String.Empty;

            if (locations == null || locations.Length == 0)
                throw new InvalidOperationException();

            bool nameRepresentsPath = IsSpecificPath(name);
            string cacheKey = CreateCacheKey(cacheKeyPrefix, name, (nameRepresentsPath) ? String.Empty : controllerName);

            if (useCache)
            {
                string result = ViewLocationCache.GetViewLocation(controllerContext.HttpContext, cacheKey);
                if (result != null)
                {
                    return result;
                }
            }

            return (nameRepresentsPath) ?
                GetPathFromSpecificName(controllerContext, name, cacheKey, ref searchedLocations) :
                GetPathFromGeneralName(controllerContext, locations, name, controllerName, cacheKey, ref searchedLocations);
        }

        private string GetPathFromGeneralName(ControllerContext controllerContext, string[] locations, string name, string controllerName, string cacheKey, ref string[] searchedLocations)
        {
            string result = String.Empty;
            searchedLocations = new string[locations.Length];
            string language = controllerContext.RouteData.Values["lang"].ToString();

            for (int i = 0; i < locations.Length; i++)
            {
                string virtualPath = String.Format(CultureInfo.InvariantCulture, locations[i], name, controllerName,language);

                if (FileExists(controllerContext, virtualPath))
                {
                    searchedLocations = _emptyLocations;
                    result = virtualPath;
                    ViewLocationCache.InsertViewLocation(controllerContext.HttpContext, cacheKey, result);
                    break;
                }

                searchedLocations[i] = virtualPath;
            }

            return result;
        }

        private string CreateCacheKey(string prefix, string name, string controllerName)
        {
            return String.Format(CultureInfo.InvariantCulture, _cacheKeyFormat,
                GetType().AssemblyQualifiedName, prefix, name, controllerName);
        }

        private string GetPathFromSpecificName(ControllerContext controllerContext, string name, string cacheKey, ref string[] searchedLocations)
        {
            string result = name;

            if (!FileExists(controllerContext, name))
            {
                result = String.Empty;
                searchedLocations = new[] { name };
            }

            ViewLocationCache.InsertViewLocation(controllerContext.HttpContext, cacheKey, result);
            return result;
        }

        private static bool IsSpecificPath(string name)
        {
            char c = name[0];
            return (c == '~' || c == '/');
        }

    }
}

使用System.Web.Mvc；
使用制度；
使用System.Web.Hosting；
利用制度全球化；
使用System.Linq；
命名空间MvcLocalization
{
公共类本地化WebFormViewEngine:WebFormViewEngine
{
私有常量字符串_cacheKeyFormat=“：ViewCacheEntry:{0}:{1}:{2}:{3}:”；
私有常量字符串\u cacheKeyPrefix\u Master=“Master”；
私有常量字符串\u cacheKeyPrefix\u Partial=“Partial”；
私有常量字符串\u cacheKeyPrefix\u View=“View”；
私有静态只读字符串[]_emptyLocations=新字符串[0]；
公共本地化WebFormViewEngine（）
{
base.ViewLocationFormats=新字符串[]{
“~/Views/{1}/{2}/{0}.aspx”，
“~/Views/{1}/{2}/{0}.ascx”，
“~/Views/Shared/{2}/{0}.aspx”，
“~/Views/Shared/{2}/{0}.ascx”，
“~/Views/{1}/{0}.aspx”，
“~/Views/{1}/{0}.ascx”，
“~/Views/Shared/{0}.aspx”，
“~/Views/Shared/{0}.ascx”
};
}
私有VirtualPathProvider_vpp；
public override ViewEngineResult FindView（ControllerContext ControllerContext、string viewName、string masterName、bool useCache）
{
如果（controllerContext==null）
抛出新ArgumentNullException（“controllerContext”）；
if（String.IsNullOrEmpty（viewName））
抛出新ArgumentException（“viewName”）；
字符串[]viewLocationsSearched；
字符串[]主位置搜索；
string controllerName=controllerContext.RoutedData.GetRequiredString（“控制器”）；
字符串viewPath=GetPath（controllerContext、ViewLocationFormats、“ViewLocationFormats”、viewName、controllerName、_-cacheKeyPrefix_-View、useCache、out-viewLocationsSearched）；
字符串masterPath=GetPath（controllerContext，MasterLocationFormats，“MasterLocationFormats”，masterName，controllerName，_cacheKeyPrefix_Master，useCache，out masterLocationsSearched）；
if（String.IsNullOrEmpty（viewPath）| |（String.IsNullOrEmpty（masterPath）&&！String.IsNullOrEmpty（masterName）））
{
返回新的ViewEngineResult（viewLocationsSearched.Union（masterLocationsSearched））；
}
返回新的ViewEngineResult（CreateView（controllerContext、viewPath、masterPath），此选项为；
}
私有字符串GetPath（ControllerContext ControllerContext，字符串[]位置，字符串位置PropertyName，字符串名称，字符串controllerName，字符串cacheKeyPrefix，bool useCache，out字符串[]搜索位置）
{
搜索位置=_清空位置；
if（String.IsNullOrEmpty（name））
返回字符串。空；
如果（位置==null | |位置。长度==0）
抛出新的InvalidOperationException（）；
bool nameRepresentsPath=IsSpecificPath（名称）；
string cacheKey=CreateCacheKey（cacheKeyPrefix，名称，（nameRepresentsPath）？string.Empty:controllerName）；
如果（使用缓存）
{
字符串结果=ViewLocationCache.GetViewLocation（controllerContext.HttpContext，cacheKey）；
如果（结果！=null）
{
返回结果；
}
}
返回（名称代表SPATH）？
GetPathFromSpecificName（controllerContext、name、cacheKey、ref searchedLocations）：
GetPathFromGeneralName（controllerContext、位置、名称、controllerName、cacheKey、ref searchedLocations）；
}
私有字符串GetPathFromGeneralName（ControllerContext ControllerContext，string[]位置，string名称，string controllerName，string cacheKey，ref string[]searchedLocations）
{
字符串结果=string.Empty；
searchedLocations=新字符串[locations.Length]；
string language=controllerContext.RouteData.Values[“lang”].ToString（）；
对于（int i=0；ipublic LocalizationWebFormViewEngine() 
{
    base.PartialViewLocationFormats = new string[] {
        "~/Views/{2}/{1}/{0}.cshtml", 
        "~/Views/{2}/{1}/{0}.aspx", 
        "~/Views/{2}/Shared/{0}.cshtml", 
        "~/Views/{2}/Shared/{0}.aspx"
    };

    base.ViewLocationFormats = new string[] {
        "~/Views/{2}/{1}/{0}.cshtml", 
        "~/Views/{2}/{1}/{0}.aspx", 
        "~/Views/{2}/Shared/{0}.cshtml", 
        "~/Views/{2}/Shared/{0}.aspx"
    };
}

public override ViewEngineResult FindPartialView(ControllerContext controllerContext, String partialViewName, Boolean useCache)
{
    if (controllerContext == null)
    {
        throw new ArgumentNullException("controllerContext");
    }
    if (String.IsNullOrEmpty(partialViewName))
    {
        throw new ArgumentException("partialViewName");
    }

    string[] partialViewLocationsSearched;

    string controllerName = controllerContext.RouteData.GetRequiredString("controller");
    string partialPath = GetPath(controllerContext, PartialViewLocationFormats, "PartialViewLocationFormats", partialViewName, controllerName, _cacheKeyPrefix_Partial, useCache, out partialViewLocationsSearched);

    return new ViewEngineResult(CreatePartialView(controllerContext, partialPath), this);}
}

public class LocalizedViewEngine : RazorViewEngine
{
    private string[] _defaultViewLocationFormats;

    public LocalizedViewEngine()
        : base()
    {
        // Store the default locations which will be used to append
        // the localized view locations based on the thread Culture
        _defaultViewLocationFormats = base.ViewLocationFormats;
    }

    public override ViewEngineResult FindPartialView(ControllerContext controllerContext, string partialViewName, bool useCache)
    {
        AppendLocalizedLocations();
        return base.FindPartialView(controllerContext, partialViewName, useCache:fase);
    }

    public override ViewEngineResult FindView(ControllerContext controllerContext, string viewName, string masterName, bool useCache)
    {
        AppendLocalizedLocations();
        returnbase.FindView(controllerContext, viewName, masterName, useCache:false);
    }

    private void AppendLocalizedLocations()
    {
        // Use language two letter name to identify the localized view
        string lang = Thread.CurrentThread.CurrentUICulture.TwoLetterISOLanguageName;

        // Localized views will be in the format "{action}.{lang}.cshtml"
        string localizedExtension = string.Format(".{0}.cshtml", lang);

        // Create an entry for views and layouts using localized extension
        string view =  "~/Views/{1}/{0}.cshtml".Replace(".cshtml", localizedExtension);
        string shared =  "~/Views/{1}/Shared/{0}".Replace(".cshtml", localizedExtension);

        // Create a copy of the default view locations to modify
        var list = _defaultViewLocationFormats.ToList();

        // Insert the new locations at the top of the list of locations
        // so they're used before non-localized views.
        list.Insert(0, shared);
        list.Insert(0, view);
        base.ViewLocationFormats = list.ToArray();
    }
}

protected void Application_Start()
{
    ...
    // Allow looking up views in ~/Features/ directory
    var razorEngine = ViewEngines.Engines.OfType<RazorViewEngine>().First();
    razorEngine.ViewLocationFormats = razorEngine.ViewLocationFormats.Concat(new string[] 
    { 
        "~/Features/{1}/{0}.cshtml"
    }).ToArray();
    ...
    // also: razorEngine.PartialViewLocationFormats if required
}

ViewLocationFormats = new string[]
{
    "~/Views/{1}/{0}.cshtml",
    "~/Views/{1}/{0}.vbhtml",
    "~/Views/Shared/{0}.cshtml",
    "~/Views/Shared/{0}.vbhtml"
};