2
SOLUTION 我并没有对新类型指定构造参数，使.NET假设类型的基类的，但它不也是他们的名字一样，所以当统一试过参数[x] .Name它得到一个空值而不是参数名称。团结不能解决动态创建类的实例
对不起，使用“U”这个词，但这真的是一个问题，我需要紧急解决这个问题，以解决其他地方的大量内存泄漏（长篇故事）。所以，如果任何人都可以提供帮助，我将非常感激它！
我在运行时使用Reflection.Emit动态创建一个类型。动态类型从运行时指定的基类型下降，并实现IController。目的是将调用包装到IController。执行一个try ... finally并最终处理一个对象。
这是奇怪的。我可以像这样
var requiredDependency = new Logger();
Type interceptingControllerType = CreateInterceptingControllerType(superClass);
var constructorInfo = interceptingControllerType.GetConstructor(new Type[] { typeof(Logger) });
var result = (IController)constructorInfo.Invoke(new object[] { requiredDependency });
我还可以使用统一解决超像这样
var superClassThatWillResolve = container.Resolve(superClass);
创建这个新类型的实例但我无法用团结来解决动态创建的子类
var newSubClassThatWontResolve = container.Resolve(interceptingControllerType);
当我尝试后我得到下面的异常
Microsoft.Practices.Unity.ResolutionFailedException was unhandled
Message=Resolution of the dependency failed, type = "9d206a0c-2c78-43d1-8907-8227ad1242f1", name = "(none)".
Exception occurred while: while resolving.
Exception is: ArgumentNullException - Value cannot be null.
Parameter name: str
-----------------------------------------------
At the time of the exception, the container was:
Resolving 9d206a0c-2c78-43d1-8907-8227ad1242f1,(none)
Source=Microsoft.Practices.Unity
TypeRequested=9d206a0c-2c78-43d1-8907-8227ad1242f1
StackTrace:
at Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, Object existing, String name, IEnumerable`1 resolverOverrides)
at Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, String name, IEnumerable`1 resolverOverrides)
at Microsoft.Practices.Unity.UnityContainer.Resolve(Type t, String name, ResolverOverride[] resolverOverrides)
at Microsoft.Practices.Unity.UnityContainerExtensions.Resolve(IUnityContainer container, Type t, ResolverOverride[] overrides)
at ConsoleApplication18.InterceptingControllerBuilder.CreateControllerInterceptor(IUnityContainer container, Type superClass) in C:\Users\PeterMorris\Documents\Visual Studio 2010\Projects\ConsoleApplication18\InterceptingControllerBuilder.cs:line 24
at ConsoleApplication18.Program.Main(String[] args) in C:\Users\PeterMorris\Documents\Visual Studio 2010\Projects\ConsoleApplication18\Program.cs:line 15
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()
InnerException: System.ArgumentNullException
Message=Value cannot be null.
Parameter name: str
Source=mscorlib
ParamName=str
StackTrace:
at System.Reflection.Emit.DynamicILGenerator.Emit(OpCode opcode, String str)
at Microsoft.Practices.ObjectBuilder2.DynamicMethodConstructorStrategy.PreBuildUp(IBuilderContext context)
at Microsoft.Practices.ObjectBuilder2.StrategyChain.ExecuteBuildUp(IBuilderContext context)
at Microsoft.Practices.ObjectBuilder2.DynamicMethodBuildPlanCreatorPolicy.CreatePlan(IBuilderContext context, NamedTypeBuildKey buildKey)
at Microsoft.Practices.ObjectBuilder2.BuildPlanStrategy.PreBuildUp(IBuilderContext context)
at Microsoft.Practices.ObjectBuilder2.StrategyChain.ExecuteBuildUp(IBuilderContext context)
at Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, Object existing, String name, IEnumerable`1 resolverOverrides)
InnerException:
下面是测试代码...
using System;
using Microsoft.Practices.Unity;
namespace ConsoleApplication18
{
class Program
{
static void Main(string[] args)
{
var container = new UnityContainer();
var childContainer = container.CreateChildContainer();
IController interceptingController = InterceptingControllerBuilder.CreateControllerInterceptor(
childContainer, typeof(CountryController));
try
{
interceptingController.Execute("Hello");
}
catch (Exception e)
{
Console.WriteLine("Exception: " + e.Message);
}
Console.ReadLine();
}
}
public class Logger
{
public void Log(string text)
{
Console.WriteLine(text);
}
}
public interface IController
{
void Execute(string text);
}
public class Controller : IController
{
readonly Logger Logger;
public Controller(Logger logger)
{
Logger = logger;
}
public virtual void Execute(string text)
{
Logger.Log("Controller: " + text);
}
}
public class CountryController : Controller
{
public CountryController(Logger logger)
: base(logger)
{
}
public override void Execute(string text)
{
base.Execute("CountryController: " + text);
}
}
}
而且实现代码
using Microsoft.Practices.Unity;
namespace ConsoleApplication18
{
public interface IUnityContainerController
{
IUnityContainer IUnityContainerController_UnityContainer { get; set; }
}
}
using System;
using System.Linq;
using System.Reflection;
using System.Reflection.Emit;
using Microsoft.Practices.Unity;
namespace ConsoleApplication18
{
public static class InterceptingControllerBuilder
{
const string UnityContainerBackingFieldName = "IUnityContainerController_BackingField";
static MethodInfo DisposeMethodInfo = typeof(IDisposable).GetMethod("Dispose");
public static IController CreateControllerInterceptor(IUnityContainer container, Type superClass)
{
var requiredDependency = new Logger();
Type interceptingControllerType = CreateInterceptingControllerType(superClass);
var constructorInfo = interceptingControllerType.GetConstructor(new Type[] { typeof(Logger) });
var result = (IController)constructorInfo.Invoke(new object[] { requiredDependency });
var resultAsIUnityContainerController = (IUnityContainerController)result;
resultAsIUnityContainerController.IUnityContainerController_UnityContainer = container;
var superClassThatWillResolve = container.Resolve(superClass);
var newSubClassThatWontResolve = container.Resolve(interceptingControllerType);
return result;
}
static Type CreateInterceptingControllerType(Type superClass)
{
if (!typeof(IController).IsAssignableFrom(superClass))
throw new ArgumentException("SuperClass does not implement IController");
string guid = Guid.NewGuid().ToString();
var assemblyName = new AssemblyName(guid);
var assemblyBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(
assemblyName,
AssemblyBuilderAccess.Run);
var moduleBuilder = assemblyBuilder.DefineDynamicModule(guid);
var typeBuilder = moduleBuilder.DefineType(
guid,
TypeAttributes.Class | TypeAttributes.Public,
superClass);
CreateConstructor(superClass, typeBuilder);
FieldBuilder unityContainerBackingFieldBuilder;
ImplementIUnityContainerController(typeBuilder, out unityContainerBackingFieldBuilder);
ImplementIController(superClass, typeBuilder, unityContainerBackingFieldBuilder);
return typeBuilder.CreateType();
}
static void CreateConstructor(Type superClass, TypeBuilder typeBuilder)
{
var constructorInfo = superClass.GetConstructors()
.OrderByDescending(x => x.GetParameters().Count())
.FirstOrDefault();
if (constructorInfo == null)
return;
ParameterInfo[] constructorParameters =
constructorInfo.GetParameters().ToArray();
Type[] parameterTypes = constructorParameters.Select(x => x.ParameterType).ToArray();
var constructorBuilder = typeBuilder.DefineConstructor(
MethodAttributes.Public,
CallingConventions.Standard,
parameterTypes);
var bodyGenerator = constructorBuilder.GetILGenerator();
bodyGenerator.Emit(OpCodes.Ldarg_0);
for (int argumentIndex = 0; argumentIndex < constructorParameters.Count(); argumentIndex++)
bodyGenerator.Emit(OpCodes.Ldarg, argumentIndex + 1);
bodyGenerator.Emit(OpCodes.Call, constructorInfo);
bodyGenerator.Emit(OpCodes.Ret);
}
static void ImplementIUnityContainerController(TypeBuilder typeBuilder, out FieldBuilder unityContainerBackingFieldBuilder)
{
typeBuilder.AddInterfaceImplementation(typeof(IUnityContainerController));
unityContainerBackingFieldBuilder = typeBuilder.DefineField(
UnityContainerBackingFieldName,
typeof(IUnityContainer),
FieldAttributes.Private);
var propertyAccessorAttributes =
MethodAttributes.Public | MethodAttributes.SpecialName |
MethodAttributes.HideBySig | MethodAttributes.Virtual;
var getterBuilder = typeBuilder.DefineMethod(
"get_IUnityContainerController_UnityContainer",
propertyAccessorAttributes,
typeof(IUnityContainer),
Type.EmptyTypes);
var getterGenerator = getterBuilder.GetILGenerator();
getterGenerator.Emit(OpCodes.Ldarg_0);
getterGenerator.Emit(OpCodes.Ldfld, unityContainerBackingFieldBuilder);
getterGenerator.Emit(OpCodes.Ret);
var setterBuilder = typeBuilder.DefineMethod(
"set_IUnityContainerController_UnityContainer",
propertyAccessorAttributes,
null,
new Type[] { typeof(IUnityContainer) });
var setterGenerator = setterBuilder.GetILGenerator();
setterGenerator.Emit(OpCodes.Ldarg_0);
setterGenerator.Emit(OpCodes.Ldarg_1);
setterGenerator.Emit(OpCodes.Stfld, unityContainerBackingFieldBuilder);
setterGenerator.Emit(OpCodes.Ret);
}
static void ImplementIController(Type superClass, TypeBuilder typeBuilder, FieldBuilder unityContainerBackingFieldBuilder)
{
typeBuilder.AddInterfaceImplementation(typeof(IController));
MethodInfo interfaceMethod = typeof(IController).GetMethod("Execute");
InterfaceMapping mapping = superClass.GetInterfaceMap(typeof(IController));
MethodInfo baseMethod = mapping.TargetMethods.Single();
var methodBuilder = typeBuilder.DefineMethod(
typeof(IController).Name + ".Execute",
MethodAttributes.Public | MethodAttributes.Virtual |
MethodAttributes.ReuseSlot | MethodAttributes.HideBySig,
null,
new Type[] { typeof(string) });
var bodyGenerator = methodBuilder.GetILGenerator();
bodyGenerator.BeginExceptionBlock();
bodyGenerator.Emit(OpCodes.Ldarg_0);
bodyGenerator.Emit(OpCodes.Ldarg_1);
bodyGenerator.Emit(OpCodes.Call, baseMethod);
bodyGenerator.BeginFinallyBlock();
bodyGenerator.Emit(OpCodes.Ldarg_0);
bodyGenerator.Emit(OpCodes.Ldfld, unityContainerBackingFieldBuilder);
bodyGenerator.Emit(OpCodes.Call, DisposeMethodInfo);
bodyGenerator.EndExceptionBlock();
bodyGenerator.Emit(OpCodes.Ret);
typeBuilder.DefineMethodOverride(methodBuilder, interfaceMethod);
}
}
}
更新：如果超类没有参数，我不会收到错误。 – 2010-12-18 20:23:47