You can directly create a mixed manage project using ObjectARX wizard. The steps below apply to projects which are being migrating from old releases or converting a unmanaged ObjectARX project to a mixed managed.
The first thing to do is to turn on the /CLR compiler setting to compile as managed.
In the project properties window, under the Property Pages for the project, make the following modifications:
C++ : General:
Compile As Managed
From: Not using managed extensions
To: Assembly Support (/clr)
Debug Information Format: (Debug only)
From: Program Database for Edit & Continue (/ZI)
To: Program Database (/Zi)
Code Generation (Debug only):
Basic runtime checks
From: Both (/RTC1, equip, to /RTC Su...)
To: default
Precompiled Header:
Create/Use Precompiled Header
From: Automatically Generate (/YX)
To: Create Precompiled Header (/Yc)
Code Generation:
Enable Minimal Rebuild
From: Yes (/Gm)
To: No
Link with the /NOENTRY flag
In stdafx.h add:
#using <mscorlib.dll>
#using <System.dll>
#using <System.Drawing.dll>
#using <system.windows.forms.dll>
In the CPP file where you're going to use managed code, add the following after the compiler references through to stdafx.h
using namespace System;
using namespace System::Reflection;
using namespace System::Collections;
using namespace System::ComponentModel;
using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System::Security::Policy;
using namespace System::Runtime::InteropServices;
See attached sample for more details.