asp.net - 如何为自动 C++/CLI 应用程序域指定 ASP.NET 探测路径？

Question

我有一个 C++/CLI DLL，需要在 ASP.NET WebApi 操作的上下文中运行。

该操作受到使用 log4net 的 LogicalThreadContext 的 ActionFilter 的影响设置包含请求 ID 的属性；这可以很好地将请求 ID 写入日志条目。

问题在于，当需要从 C++/CLI dll 加载类时，ASP.NET 似乎正在创建一个应用程序域。 (我似乎找不到任何有关其工作原理的文档；我很想找到一些文档。)当 appdomain 管道尝试反序列化所有内容时，它会因为找不到 log4net.dll 而窒息(请参阅下面的堆栈跟踪) .

Fusion 日志显示它正在查找 C:\Windows\System32\inetsrv ，这是不正确的...我希望它在探测路径中或沿着 %PATH% 查找环境变量。

一些数据点:

• log4net.dll 可在网络应用程序的 bin 中找到。目录，并且适用于我使用它的其他所有内容。
• C++/CLI 代码不依赖于 log4net。
• 如果我注释掉对 log4net.LogicalThreadContext.Properties[...] 的通话，一切正常。
• 如果我从我的bin复制log4net.dll文件夹到C:\Windows\system32\inetsrv ，一切正常。
• web.config 文件使用 <probing privatePath="bin"/> 指定探测路径。元素。

• 我的Application_Start global.asax.cs中的方法前置 Web 应用程序的 bin目录到%PATH%环境变量:

      var currentPathEnvVar = Environment.GetEnvironmentVariable("PATH");
      var binPath = Path.Combine(Server.MapPath("~") ?? String.Empty, "bin");
      _log.DebugFormat("Prepending paths to PATH: [{0}]", binPath);
      Environment.SetEnvironmentVariable("PATH", String.Concat(binPath, Path.PathSeparator, currentPathEnvVar));
  

• 日志显示%PATH%已正确添加前缀:

  2015-06-05 17:07:48,816 1   DEBUG   MyNamespace.WebApiApplication   (null)  Prepending paths to PATH: [C:\Program Files\MyCompany\MyApp\web\bin]
  

那么如何让 ASP.NET 创建的应用程序域在正确的位置查找以加载程序集？

谢谢。

<小时/>

这是当所有这些都发生故障时记录的堆栈跟踪。

2015-06-05 17:08:41,148 23  ERROR   MyNamespace.MyController    (null)  Controller action failed
System.TypeInitializationException: The type initializer for '<Module>' threw an exception. ---> <CrtImplementationDetails>.ModuleLoadException: The C++ module failed to load while attempting to initialize the default appdomain.
 ---> System.Runtime.Serialization.SerializationException: Unable to find assembly 'log4net, Version=1.2.13.0, Culture=neutral, PublicKeyToken=669e0ddf0bb1aa2a'.

Server stack trace: 
   at System.Runtime.Serialization.Formatters.Binary.BinaryAssemblyInfo.GetAssembly()
   at System.Runtime.Serialization.Formatters.Binary.ObjectReader.GetType(BinaryAssemblyInfo assemblyInfo, String name)
   at System.Runtime.Serialization.Formatters.Binary.ObjectMap..ctor(String objectName, String[] memberNames, BinaryTypeEnum[] binaryTypeEnumA, Object[] typeInformationA, Int32[] memberAssemIds, ObjectReader objectReader, Int32 objectId, BinaryAssemblyInfo assemblyInfo, SizedArray assemIdToAssemblyTable)
   at System.Runtime.Serialization.Formatters.Binary.__BinaryParser.ReadObjectWithMapTyped(BinaryObjectWithMapTyped record)
   at System.Runtime.Serialization.Formatters.Binary.__BinaryParser.Run()
   at System.Runtime.Serialization.Formatters.Binary.ObjectReader.Deserialize(HeaderHandler handler, __BinaryParser serParser, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage)
   at System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream serializationStream, HeaderHandler handler, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage)
   at System.Runtime.Remoting.Channels.CrossAppDomainSerializer.DeserializeObject(MemoryStream stm)
   at System.Runtime.Remoting.Messaging.SmuggledMethodCallMessage.FixupForNewAppDomain()
   at System.Runtime.Remoting.Channels.CrossAppDomainSink.DoDispatch(Byte[] reqStmBuff, SmuggledMethodCallMessage smuggledMcm, SmuggledMethodReturnMessage& smuggledMrm)
   at System.Runtime.Remoting.Channels.CrossAppDomainSink.DoTransitionDispatchCallback(Object[] args)

Exception rethrown at [0]: 
   at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
   at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
   at System.AppDomain.IsDefaultAppDomain()
   at <CrtImplementationDetails>.GetDefaultDomain() in f:\dd\vctools\crt\crtw32\h\minternal.h:line 367
   at <CrtImplementationDetails>.DoCallBackInDefaultDomain(IntPtr function, Void* cookie) in f:\dd\vctools\crt\crtw32\h\minternal.h:line 401
   at <CrtImplementationDetails>.DefaultDomain.Initialize() in f:\dd\vctools\crt\crtw32\msilcrt\mstartup.cpp:line 278
   at <CrtImplementationDetails>.LanguageSupport.InitializeDefaultAppDomain(LanguageSupport* ) in f:\dd\vctools\crt\crtw32\msilcrt\mstartup.cpp:line 343
   at <CrtImplementationDetails>.LanguageSupport._Initialize(LanguageSupport* ) in f:\dd\vctools\crt\crtw32\msilcrt\mstartup.cpp:line 546
   at <CrtImplementationDetails>.LanguageSupport.Initialize(LanguageSupport* ) in f:\dd\vctools\crt\crtw32\msilcrt\mstartup.cpp:line 703
   --- End of inner exception stack trace ---
   at <CrtImplementationDetails>.ThrowModuleLoadException(String errorMessage, Exception innerException) in f:\dd\vctools\crt\crtw32\h\minternal.h:line 194
   at <CrtImplementationDetails>.LanguageSupport.Initialize(LanguageSupport* ) in f:\dd\vctools\crt\crtw32\msilcrt\mstartup.cpp:line 713
   at .cctor() in f:\dd\vctools\crt\crtw32\msilcrt\mstartup.cpp:line 754
   --- End of inner exception stack trace ---
   at MyNamespace.MyController.MyAction(String foo, Int64 bar, String baz)

Answer 1

这帮助我解决了类似的问题: https://blogs.msdn.microsoft.com/jorman/2007/08/31/loading-c-assemblies-in-asp-net/ 面临的选项 2.a 和建议的解决方案工作正常:

protected void Application_Start(object sender, EventArgs e){ String _path = String.Concat(System.Environment.GetEnvironmentVariable("PATH"), ";", System.AppDomain.CurrentDomain.RelativeSearchPath); System.Environment.SetEnvironmentVariable("PATH", _path, EnvironmentVariableTarget.Process); }