BUG: An exception error occurs when you pass VARIANT parameters by reference to an MFC IDispatch COM Component in Visual Studio .NET 2002 (312910)

HRESULT _stdcall Method1(
                [in, out] VARIANT* inoutVal, 
                [out] VARIANT* outVal, 
                [out, retval] VARIANT* retVal);

WORKAROUND

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The following sample C# code describes this workaround:

using MyMFCLibrary;
using System.Reflection;

public class MyClass
{
  MyMFCAutomationServer objTest = new MyMFCAutomationServerDoc();
 
 object [] arglist = { "Hello World!" };

 ParameterModifier pm = new ParameterModifier(1);
 
 //Set the VT_BYREF flag on the first parameter.
 pm[0] = true; 

 //Create an array of ParameterModifier objects, and then put in your element.
 ParameterModifier [] pmArray = { pm };
 
 //Use late binding and call the method.
 objTest.GetType().InvokeMember("VariantByRef",
                                 BindingFlags.InvokeMethod, 
                                 null, 
                                 objTest, 
                                 arglist, 
                                 pmArray, 
                                 null, 
                                 null);
}