无法在Mono中加载类型“System.Web.Http.WebHost.Routing.HttpRouteExceptionHandler”

Question

我尝试在Mono中使用最新的Asp.Net Web API，但是出现了以下错误：

System.TypeLoadException
Could not load type 'System.Web.Http.WebHost.Routing.HttpRouteExceptionHandler' from assembly 'System.Web.Http.WebHost, Version=5.1.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'.

Description: HTTP 500.Error processing request.
Details: Non-web exception. Exception origin (name of application or object): System.Web.
Exception stack trace:
  at System.Web.Routing.UrlRoutingModule.PostResolveRequestCache (System.Web.HttpContextBase context) [0x00054] in /Volumes/build-root-ramdisk/mono-3.4.0/mcs/class/System.Web.Routing/System.Web.Routing/UrlRoutingModule.cs:128 
  at System.Web.Routing.UrlRoutingModule.PostResolveRequestCache (System.Object o, System.EventArgs e) [0x00007] in /Volumes/build-root-ramdisk/mono-3.4.0/mcs/class/System.Web.Routing/System.Web.Routing/UrlRoutingModule.cs:88 
  at System.Web.HttpApplication+<RunHooks>c__Iterator0.MoveNext () [0x001ba] in /Volumes/build-root-ramdisk/mono-3.4.0/mcs/class/System.Web/System.Web/HttpApplication.cs:1050 
  at System.Web.HttpApplication+<Pipeline>c__Iterator1.MoveNext () [0x0073b] in /Volumes/build-root-ramdisk/mono-3.4.0/mcs/class/System.Web/System.Web/HttpApplication.cs:1260 
  at System.Web.HttpApplication.Tick () [0x00000] in /Volumes/build-root-ramdisk/mono-3.4.0/mcs/class/System.Web/System.Web/HttpApplication.cs:932 

Version Information: 3.4.0 ((no/c3fc3ba Thu May 1 22:52:17 EDT 2014); ASP.NET Version: 4.0.30319.17020

我应该通过Nuget包括哪些dll？目前我已经引用了以下程序集：

- System (from GAC)
- System.Web (from GAC)
- System.Web.Http (from Nuget)
- System.Net.Http.Formatting (from Nuget)
- System.Web.Http.WebHost (from Nuget)
- Newtonsoft.Json (from Nuget)

- Jerry Bian

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可能是重复的问题：无法在Mono / xsp4中加载类型'System.Web.Http.WebHost.HttpControllerHandler' - Lex Li

Answer 1

在Xamarin的bugzilla中存在一个类似的bug。显然，需要先更新Mono aspnetwebstack才能使用最新的Web API库：

https://bugzilla.xamarin.com/show_bug.cgi?id=19314

- Vadim

Answer 2

我猜我回答有点晚了，但是我刚刚遇到了类似的问题，为了调试，我在源代码中添加了以下行：

var httpHost = new System.Web.Http.WebHost.HttpControllerHandler(null);

编译失败了，出现了以下错误（此处换行是我添加的）：

Global.asax.cs(116,56): error CS1684: Reference to type
 `System.Web.HttpTaskAsyncHandler' claims it is defined assembly 
 `System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a',
  but it could not be found

基本上是这样的 - 是的。Busted System.Web.dll

- galets

Answer 3

这个问题可能可以通过不使用config.MapHttpAttributeRoutes();，而是手动指定Web API路由（例如config.Routes.MapHttpRoute...）来解决。

- Chris Simpson