Calling VB6 method from C# from dynamic object with ByRef and optional Parameters

Question

I usually make calls to class methods dynamically without problems, but only this method not works, always return error:

Dynamic conn = Activator.CreateInstance(Type.GetTypeFromProgID("MyTeam.MyClass"));
bool test = false;
conn.MyFunction(100,"test",DateTime.Now, test, test, "another","another","another");

Original Method of external class with VB:

Public Function MyFunction(ByVal Id As Integer, ByVal Var1 As String, ByVal Fecha As Date, 
                                   Optional ByRef Opcion1 As Boolean = False, 
                                   Optional ByRef Opcion2 As Boolean = False, 
                                   Optional ByVal Var1 As String = "", 
                                   Optional ByVal Var2 As String = "",
                                   Optional ByVal Var3 As String = "" ) As String

Question 1: Is it possible to omit optional parameters?
Question 2: Is it possible call with ByRef parameters in other way?

UPDATE 1: Yes, C# supports ref/out parameters, but... variables of type "dynamic" calling Method, support this type of input?

Include the error in your question so we know what problem you are trying to solve. — BlueMonkMN, Jan 10 '18 at 14:01
Possible duplicate of [C# 4.0 optional out/ref arguments](https://stackoverflow.com/questions/2870544/c-sharp-4-0-optional-out-ref-arguments) — BlueMonkMN, Jan 10 '18 at 14:33
Of course, C# supports this type of parameters, but not with "dynamic" objects? Function return "arguments not valid" — MainMind, Jan 11 '18 at 06:40

score 1 · Accepted Answer · answered Jan 10 '18 at 14:40

1

In order to pass byref in c# you need to precede the parameter with ref when you call the function too.

conn.MyFunction(100,"test",DateTime.Now, ref test, ref test, "another","another","another");

answered Jan 10 '18 at 14:40

BlueMonkMN

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C# works seamlessly with references, the DYNAMIC object encapsulates the complexity of translating these references. **The problem was the VB6 method itself**!!! solved. – MainMind Jan 11 '18 at 13:51

Calling VB6 method from C# from dynamic object with ByRef and optional Parameters

1 Answers1