无法从动态生成的程序集中访问 CodeBase

Question

我正在尝试在 .Net 中动态创建程序集。但是，我似乎无法弄清楚如何让 CodeBase 属性返回一个值。这是一个例子：

var assemblyName = new AssemblyName
                        {
                            Name = "Whatever",
                            CodeBase = Directory.GetCurrentDirectory()
                        };
var assemblyBuilder = AppDomain.CurrentDomain
    .DefineDynamicAssembly(assemblyName, AssemblyBuilderAccess.RunAndSave);
var moduleBuilder = assemblyBuilder.DefineDynamicModule("WhateverModule", "Whatever.dll");
var typeBuilder = moduleBuilder.DefineType("WhateverType", TypeAttributes.Public);
var type = typeBuilder.CreateType();
assemblyBuilder.Save("Whatever.dll");
var codeBase = type.Assembly.CodeBase; // throws the below exception

System.NotSupportedException was unhandled
  Message=The invoked member is not supported in a dynamic assembly.
  Source=mscorlib
  StackTrace:
       at System.Reflection.Emit.InternalAssemblyBuilder.get_CodeBase()
       at Stupid.Program.Main(String[] args) in C:\Users\Walking Disaster\Documents\Visual Studio 10\Projects\Lingual.Proxy\Stupid\Program.cs:line 25
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()

谁能看出我做错了什么？

说明：我正在尝试使用在运行时生成测试方法的插件来扩展 NUnit。它通过获取一组 Action 委托来实现这一点。不幸的是，Reflection 已经深入到框架中，所以我不得不为每个 Action 委托发出带有方法的类。当我只使用 NUnitTestMethod 类时，这很好用，但是当我使用 NUnitTestFixture 时，它​​会失败，因为它试图从程序集中读取 CodeBase。我不想创建一个物理组件，但是这个项目是一个又一个的妥协。

Answer 1

我认为异常原因是 CodeBase 在动态汇编上毫无意义。来自 MSDN：

最初指定的程序集位置

如果你重新加载程序集，它不会抛出异常：

var assemblyName = new AssemblyName
                       {
                           Name = "Whatever",
                           CodeBase = Directory.GetCurrentDirectory()
                       };
var assemblyBuilder = AppDomain.CurrentDomain
    .DefineDynamicAssembly(assemblyName, AssemblyBuilderAccess.RunAndSave);
var moduleBuilder = assemblyBuilder.DefineDynamicModule(
    "WhateverModule", "Whatever.dll");
var typeBuilder = 
                 moduleBuilder.DefineType("WhateverType", TypeAttributes.Public);
var type = typeBuilder.CreateType();
assemblyBuilder.Save("Whatever.dll");

var assembly = Assembly.LoadFrom("Whatever.dll");
var codeBase = assembly.CodeBase; // this won't throw exception

Answer 2

大会的Location 有效吗？你可以分叉 NUnit 并使用它来代替你提到的损坏：P

我已经花了几个小时来研究 NUnit 的“可扩展性”故事，无法想象曾经在 xUnit.net 上选择它 - 但我想决定因素将是你有多少测试......