[ADVANCED-DOTNET] C# : COM / late binding / Variants

[[EMAIL PROTECTED]]

Dear Sirs,

i try to call a COM object via InvokeMember() - which works for the
simple case (in parameter).

But i don't have an idea how to use soemthing like ""[out] VARIANT* ".

How can i pass an array by ref to a COM Object ?

Attached are the .cs code and the typelib. The *interesting* variable is
"quantityTotal".

best regards,
goran


----- typelib -----

// typelib filename: MyApp.tlb

[
  uuid(06688AF1-07BE-11D7-AABF-00D0B7B2802B),
  version(3.0),
  helpstring("MyApp")
]
library MyAppTypLib
{
    // TLib :     // TLib : OLE Automation :
{00020430-0000-0000-C000-000000000046}
    importlib("stdole32.tlb");

    // Forward declare all types defined in this typelib
    dispinterface INTER_AP1;
    dispinterface INTER_AP2;

    [
      uuid(06688AF2-07BE-11D7-AABF-00D0B7B2802B),
      helpstring("Dispatch Interface")
    ]
    dispinterface INTER_AP1 {
        properties:
        methods:
        [id(0x00000010)]
        short function10 (
                        [in] BSTR equipmentName,
                        [out] long* recnum,
                        [out] VARIANT* quantityTotal );
 ...
    };

    [
      uuid(06688AF3-07BE-11D7-AABF-00D0B7B2802B),
      helpstring("Dispatch Interface")
    ]
    dispinterface INTER_AP2 {
        properties:
        methods:
  ...
    };

    [
      uuid(06688AF4-07BE-11D7-AABF-00D0B7B2802B),
      helpstring("Coclass of MyApp")
    ]
    coclass my_coclass {
        [default] dispinterface INTER_AP2;
        dispinterface INTER_AP1;
    };

};


----- C# Code -----

using System;
using System.Reflection;
using System.Collections;
using System.Runtime.InteropServices;

namespace ConsoleApplication1
{

 class Class1
 {

  static void Main(string[] args)
  {

   Type objTypeMyApp = Type.GetTypeFromProgID("OLEDemo");
   object objMyAppLateBound = Activator.CreateInstance(objTypeMyApp);

   object myAppObj =  objTypeAirline.InvokeMember("MyApplication",
    BindingFlags.Default | BindingFlags.GetProperty,
    null,
    objAirlineLateBound,
    new object[]{});


   System.Int32 recnum = new System.Int32(); // Is this corrent ???
   ... quantityTotal = ... // HOW TO DEFINE THIS ???????

   ParameterModifier pm1 = new  ParameterModifier(2);
   pm1[0] = true;
   pm1[1] = false;

   ParameterModifier pm2 = new  ParameterModifier(2);
   pm2[0] = false;
   pm2[1] = true;

   ParameterModifier pm3 = new  ParameterModifier(2);
   pm3[0] = false;
   pm3[1] = true;

   object[] arrayInputEq = { "Equipment_01", recnum, quantityTotal };

   object funcObj =  myAppObj.GetType().InvokeMember("function10",
    BindingFlags.Default | BindingFlags.InvokeMethod,
    null,
    myAppObj,
    arrayInputEq, new ParameterModifier[]{pm1, pm2, pm3}, null, null );

   Console.ReadLine();
  }
 }
}

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