当应用程序根目录不同时，不会调用MVC VirtualPathProvider GetFile

Question

I have all views, scripts, styles compiled as a embedded resource in different DLL. Iam using VirtualPathProvider to get the file. The web running fine when it's places in the web root -> www.XXX.com

The problem is when i place my website to www.XXX.com/YYY It checks files in the VirtualPathProvider if they exist and yes, my files are found. My controller function which returns a View is called, but GetFile in VirtualPathProvider is not called and website says Error 404.

Routing:

public static void RegisterRoutes(RouteCollection routes)
{
    routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

    routes.MapRoute(name: "Default", namespaces: new[] {"Merz.Ems.Core.Controllers"},
        url: "{controller}/{action}", defaults: new {controller = "Index", action = "Index"});

    routes.Add(new Route("Resources/{*url}", new EmbeddedResourceRouteHandler()));
}

The EmbeddedResourceRouteHandler handles scripts and styles.

VirtualPathProvider:

using System;
using System.Collections;
using System.IO;
using System.Linq;
using System.Web;
using System.Web.Caching;
using System.Web.Hosting;
using System.Web.Routing;

namespace Merz.Ems.Core.VirtualProviders
{
public class EmbeddedVirtualPathProvider : VirtualPathProvider
{
    public class EmbeddedVirtualFile : VirtualFile
    {
        private Stream _stream;

        public EmbeddedVirtualFile(string virtualPath, Stream stream) : base(virtualPath)
        {
            if (null == stream) throw new ArgumentNullException("stream");
            _stream = stream;
        }

        public override Stream Open()
        {
            return _stream;
        }
    }

    public override CacheDependency GetCacheDependency(string virtualPath,IEnumerable virtualPathDependencies,DateTime utcStart)
    {
        string embedded = _GetEmbeddedPath(virtualPath);

        try
        {
            if (string.IsNullOrEmpty(embedded))
                return base.GetCacheDependency(virtualPath, virtualPathDependencies, utcStart);
        }
        catch
        {
            // ignored
        }

        return null;
    }

    public override bool FileExists(string virtualPath)
    {
        string embedded = _GetEmbeddedPath(virtualPath);
        bool reallyExists = File.Exists(HttpContext.Current.Server.MapPath(virtualPath));

        return reallyExists || base.FileExists(virtualPath) || !string.IsNullOrEmpty(embedded);
    }

    public override VirtualFile GetFile(string virtualPath)
    {
        string embedded = _GetEmbeddedPath(virtualPath);
        if (string.IsNullOrEmpty(embedded))
        {
            if (base.FileExists(virtualPath)) return base.GetFile(virtualPath);
            else
            {
                var path = HttpContext.Current.Server.MapPath(virtualPath);
                if (File.Exists(path))
                {
                    Stream s = File.OpenRead(path);
                    return new EmbeddedVirtualFile(virtualPath, s);
                }
            }
        }

        return new EmbeddedVirtualFile(virtualPath,GetType().Assembly.GetManifestResourceStream(embedded));
    }

    private string _GetEmbeddedPath(string path)
    {
        if (path.StartsWith("~/")) path = path.Substring(1);

        path = path.ToLowerInvariant();
        path = "Merz.Ems.Core" + path.Replace('/', '.');
        return GetType().Assembly.GetManifestResourceNames().FirstOrDefault(o => o.Equals(path, StringComparison.OrdinalIgnoreCase));
    }
}

So, why it's working if my page runs from www.xxx.com and not www.xxx.com/yyy ? (yyy is a root of the application )

Thanks :)

Answer 1

I solved my problem after lot of hours.

    private string _GetEmbeddedPath(string path)
    {
        if (path.StartsWith("~/")) path = path.Substring(1);

        if (HostingEnvironment.ApplicationVirtualPath != null)
        {
            if (path.StartsWith(HostingEnvironment.ApplicationVirtualPath)) path = path.Substring(HostingEnvironment.ApplicationVirtualPath.Length);
        }

        path = path.ToLowerInvariant();
        path = "Merz.Ems.Core" + path.Replace('/', '.');
        return GetType().Assembly.GetManifestResourceNames().FirstOrDefault(o => o.Equals(path, StringComparison.OrdinalIgnoreCase));
    }

In this function, i added

if (HostingEnvironment.ApplicationVirtualPath != null)
{
      if (path.StartsWith(HostingEnvironment.ApplicationVirtualPath)) path = path.Substring(HostingEnvironment.ApplicationVirtualPath.Length);
}

to remove the subfolder, so it finds the file without any problem. My first attempt was to filter subfolder from the virtual path in FileExists function and that was the bad way. Why ? Who knows.