无法在Mono中加载’System.Web.Http.WebHost.Routing.HttpRouteExceptionHandler’类型

我尝试在Mono中使用最新的Asp.Net Web API，但错误显示如下：

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+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+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？ 目前我引用了这些程序集：

 - 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) 

Answer 1

Xamarin bugzilla中存在类似的错误。 显然，需要首先更新Mono aspnetwebstack才能使用最新的Web API库：

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

Answer 2

我想我太迟了添加我的答案，但我只是有类似的问题，并且为了调试，我在源代码中添加了以下代码：

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

瞧，汇编失败了（换行是我的）：

 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 

所以，基本上 – 是的。 Busted System.Web.dll

Answer 3

这可能是因为不使用config.MapHttpAttributeRoutes(); ，而是手动指定Web API路由（例如config.Routes.MapHttpRoute …）。