Issue with [Csla.Reflection.MethodCaller.GetParameterTypes(object[] parameters) (csla ver 3.8.4)

Issue with [Csla.Reflection.MethodCaller.GetParameterTypes(object[] parameters) (csla ver 3.8.4)

Old forum URL:

Troncho posted on Saturday, August 30, 2014

Hi everybody.

I'm invoking public factory methods using Csla Reflection, and came across a particular case where

public static object CallFactoryMethod(Type objectType, string method, params object[] parameters)
  object returnValue;
  MethodInfo factory = objectType.GetMethod(method, factoryFlags, null
MethodCaller.GetParameterTypes(parameters), null);
 if (factory == null)

presents an issue when it calls [MethodCaller.GetParameterTypes(parameters)] and [parameters] is null.

When [GetParameterTypes(null) is executed, it adds [result.Add(typeof(object));] to the result [type] list.

public static Type[] GetParameterTypes(object[] parameters)
List<Type> result = new List<Type>();

if (parameters == null)

I have a particular case where I define 2 public static methods on a class like this:

1. public static NewObject() {...}

2. public static NewObject(object obj} {...}

By default, when I try to Invoke the 1st. method with no parameters, CallFactoryMethod(..) with [null] as params[], it defaults to the 2nd. version of the method, due to its default parameter added by GetParameterTypes(..).

And it throws an exception because I'm not sending the [object] parameter, instead, I'm sending null as params.

I didn't get to check the implications of changing this behaviour on CSLA.

If anyone can suggest a simple workaround, it's welcome.

For now I'll use my own Reflection Functions to call on this factory methods for NewObject on my BOs.

Thanks to all,


RockfordLhotka replied on Friday, September 05, 2014

It has been a long time since I've looked at that code, but it is complex to distinguish between no parameter, null parameter, and param arrays (which might be null or not). I do know there are some cases we just never figured out how to solve, and if you look at the data portal flow (for example) you'll see that we pass a second flag (or special value) to indicate the total absence of a parameter vs a null or empty param array.

Troncho replied on Friday, September 05, 2014

Thanks for your answer Rocky. You are absolutely right about it. I've just copied the code to an independant static method so I can get a parameterless constructor. The idea of an extra flag param is an excelent choice in thes cases.

Copyright (c) Marimer LLC