Dump calls

I'm working with a 3rd-party library that does some machine-specific calculations. It's called through COM interop, and takes a ton of parameters. When something doesn't come out right, it's nice to be able to quickly view what's being send in and returned without spending an excessive amount of time in the debugger... so I use this quick-and-dirty little wrapper to dump them to the output window:

using System;
using System.Collections.Generic;
using System.Text;
using System.Reflection;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Proxies;
using System.Runtime.Remoting.Messaging;
using System.Runtime.InteropServices;
using System.Diagnostics;

public class DebugTraceProxy
   : RealProxy
{
   readonly MarshalByRefObject target;

   public static T NewObject<T>()
   {
      return (T)(new DebugTraceProxy(typeof(T)).GetTransparentProxy());
   }

   private DebugTraceProxy(Type t)
      : base(t)
   {
      target = (MarshalByRefObject)Activator.CreateInstance(t);
   }
   
   public override IMessage Invoke(IMessage msg)
   {
      IMethodCallMessage call = msg as IMethodCallMessage;

      Debug.WriteLine(call.MethodName + ":");
      for (int i = 0; i < call.InArgCount; ++i)
      {
         string name = call.GetInArgName(i);
         object arg = call.GetInArg(i);
         Debug.WriteLine("   " + name + ": " + DumpOb(arg));
      }

      IMethodReturnMessage ret = RemotingServices.ExecuteMessage(target, (IMethodCallMessage)msg);

      Debug.WriteLine("Returned:");
      for (int i = 0; i < ret.OutArgCount; ++i)
      {
         string name = ret.GetOutArgName(i);
         object arg = ret.GetOutArg(i);
         Debug.WriteLine("   " + name + ": " + DumpOb(arg));
      }
            
      return ret;
   }

   private string DumpOb(object ob)
   {
      Type t = ob.GetType();
      if (t.IsPrimitive || t == typeof(string))
         return ob.ToString();

      string obDesc = "";
      FieldInfo[] infos = t.GetFields(BindingFlags.FlattenHierarchy | BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance );
      if (infos.Length == 0)
         return ob.ToString();
      foreach (FieldInfo field in infos)
      {
         if (obDesc != "")
            obDesc += ", ";
         obDesc += field.Name + ": " + field.GetValue(ob).ToString();
      }
      return obDesc;
   }
}

To use it, I create the object like so:

CrazyOb myCrazyOb = DebugTraceProxy.NewObject<crazyob>();

Reflection... handy.