Re: [Aspectsharp-users] IInvocation.Proxy and IInvocation.InvocationTarget

[hammett <ha...@uo...>]

Hello Deyan,

> I have been playing with the new IInvocation, and I noticed that both
> properties IInvocation.Proxy and IInvocation.InvocationTarget are the 
> same.
> What's there meaning, btw?

The target means: when I invoke proceed, which object will receive the 
execution; and the proxy is the proxy itself. When proxying a class, both 
values will be the same. When intercepting interfaces (using 
ProxyGenerator.CreateProxy) then the values will be different.

> What is bothering me is that there is no way to substitute the real object
> in the PreProcess method of my Interceptor, which is a part of the object
> lazy-loading process...

Well, this is easy to fix. We can make the InvocationTarget writable, but 
then the Proceed in the SameClassInvocation must be changed to something 
like:

  public override object Proceed(params object[] args)
  {
    object value = null;
    if (TargetInvocation == Proxy)
    {
      value = call.Call( args );
    }
    else
    {
      value = Method.Invoke( InvocationTarget, args );
    }
   return value;
  }

Because there is no wasy to use the delegate to invoke the method somewhere 
else. I could even generate two different delegates: one to invoke the 
base() and one to invoke anotherobject() but in this case I must know the 
Type of the anotherobject during the object generation, something like:

private void callback_1(int x)
{
  base.DoSomething(x);
}

private void otherobjectcallback(int x)
{
  // This is generated by
  // gen.Emit( OpCodes.callvirt, typeof(target).GetMethod("DoSomething", new 
type[] { typeof(int) } );
  target.DoSomething(x);
}


> I see that NHibernate also has this problem, as it
> retrieves the real object from the db and delegates (using runtime
> reflection) the calls to it. I would like to execute the methods on the 
> real
> object without runtime reflection, which means that either I can substitte
> the real object (perhaps this is the IInvocation.InvocationTarget which 
> has
> only a getter) - this I think is not possible, or populate the properties 
> of
> the proxy from the db at runtime, and then take advantage of the Dynamic
> Proxy new calling infrastructure.

Can you expose your code somewhere so we can see exactly the problem?
It will be easier to picture the solution...

--
Cheers,
hammett
http://www.digitalcraftsmen.com.br/~hammett