我在使用 Castle DynamicProxy v1.1.5.0 代理带有参数的方法时遇到问题。- 我得到异常“索引超出了数组的范围。”
如果我只使用没有参数的方法，或者 DynamicProxy v2，一切正常。
不幸的是，我无法说服我的项目的负责人向 v2 添加依赖项（我们已经在使用 NHibernate 附带的 v1）。
所以我的问题归结为：这可以在 v1 中完成吗？我用错了吗？
这是细节。
我已经实现了一种模拟继承的机制，而无需编译时对基类的依赖。请不要问为什么，原因很丑:(
这是一个完整的示例，展示了它是如何中断的。我引用的是 Castle.DynamicProxy.dll (v1)。如果我更改对 Castle.DynamicProxy[b]2[/b].dll (+ Castle.Core.dll) 的引用，请取消注释代码开头的#define。
抱歉代码太长了，但我担心我可能会泄露一些重要的细节......
另外：免责声明：代码示例有一些讨厌的错误！（可能比我发现的还要多：）
//#define DynamicProxyV2
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Reflection;
#if DynamicProxyV2
using Castle.Core.Interceptor;
#endif
using Castle.DynamicProxy;
namespace ProxyTest
{
public interface IMyInterface
{
void Foo(object a);
void Bar(object a);
void Baz(object a);
}
public interface IParam
{
string Value { get;}
}
public class DefaultImplementation : IMyInterface{
public virtual void Foo(object a) {
Console.WriteLine("Default Foo");
Bar(null);
}
public virtual void Bar(object a){
Baz(null);
}
public virtual void Baz(object a){
Console.WriteLine("Default Baz");
}
}
class DerivedImpl : ProxyDerivedImplementation {
public DerivedImpl(IMyInterface i_baseImpl)
: base(i_baseImpl) { }
public override void Foo(object a) {
Console.WriteLine("Derived - Foo!");
base.Bar(null);
}
public override void Baz(object a) {
Console.WriteLine("Derived - Baz!");
}
}
public class DoStuff {
[STAThread]
public static void Main()
{
Type t = typeof(DefaultImplementation);
IMyInterface defaultImpl = (IMyInterface)Activator.CreateInstance(t);
DerivedImpl derived = new DerivedImpl(defaultImpl);
derived.Foo(null);
}
}
public class ProxyDerivedImplementation : IMyInterface, IInterceptor {
private IMyInterface m_proxy;
public ProxyDerivedImplementation(IMyInterface i_defaultImplementation)
{
ProxyGenerator pg = new ProxyGenerator();
Type tt = i_defaultImplementation.GetType();
m_proxy = (IMyInterface)pg.CreateClassProxy(tt, this);
}
#if DynamicProxyV2
#region DynProxy v2
public void Intercept(IInvocation invocation) {
try
{
MethodInfo i_method = invocation.Method;
List<Type> types = new List<Type>();
foreach (ParameterInfo info in i_method.GetParameters())
{
types.Add(info.ParameterType);
}
MethodInfo method = this.GetType().GetMethod(i_method.Name, types.ToArray());
object[] attrs = method.GetCustomAttributes(typeof(NotOverridenAttribute), false);
if (attrs.Length > 0)
{
invocation.Proceed();
}
else
{
invocation.ReturnValue = method.Invoke(this, invocation.Arguments);
}
}
catch (Exception ex)
{
Debug.Fail(ex.Message);
//return null;
}
}
#endregion
#else
#region DynProxy v1
public object Intercept(IInvocation i_invocation, params object[] args) {
try {
MethodInfo proxiedMethod = i_invocation.Method;
List<Type> types = new List<Type>();
foreach (ParameterInfo info in proxiedMethod.GetParameters())
{
types.Add(info.ParameterType);
}
//find the corresponding method in the inheritance tree having this class as root
MethodInfo localMethod = this.GetType().GetMethod(proxiedMethod.Name, types.ToArray());
object[] attrs = localMethod.GetCustomAttributes(typeof(NotOverridenAttribute), false);
if (attrs.Length > 0)
{
//it's one of the methods in THIS class, i.e. it's not overridden
//-> we can't call the method in this class, because it will re-trigger this intercept
// and we'd get an infinite loop
// => just dispatch the method to the original proxied type
//
return i_invocation.Proceed();
}
//else we have an override for this method - call it.
return localMethod.Invoke(this, args);
} catch (Exception ex) {
Debug.Fail(ex.Message);
return null;
}
}
#endregion
#endif
[NotOverriden]
public virtual void Foo(object a) { m_proxy.Foo(a); }
[NotOverriden]
public virtual void Bar(object a) { m_proxy.Bar(a); }
[NotOverriden]
public virtual void Baz(object a) { m_proxy.Baz(a); }
}
class NotOverridenAttribute : Attribute { }
}
哇！那是一口。这是使用 v1 时发生的异常：
{"Index was outside the bounds of the array."}
[System.IndexOutOfRangeException]: {"Index was outside the bounds of the array."}
Data: {System.Collections.ListDictionaryInternal}
HelpLink: null
InnerException: null
Message: "Index was outside the bounds of the array."
Source: "DynamicAssemblyProxyGen"
StackTrace: " at CProxyTypeDefaultImplementationProxyTest0.__delegate_2.Call(Object[] )\r\n at Castle.DynamicProxy.Invocation.AbstractInvocation.Proceed(Object[] args)\r\n at ProxyTest.ProxyDerivedImplementation.Intercept(IInvocation i_invocation, Object[] args) in D:\\My Documents\\Visual Studio 2005\\Projects\\DefaultImpl\\AddedValue\\AddedValue.cs:line 133"
TargetSite: {System.Object Call(System.Object[])}
使用 v2 运行时，我得到的只是正确的输出：
派生 - Foo！衍生 - 巴兹！
...帮助？