Multi instances COM object

Question

I use a C++ written COM object in C#. I just create instance through "new". I need numerous of such objects. But every other "new" doesn't create new instance, but only gives reference on first object. Thats why I have a mess with data. Is it possible to get new instance every time? Or I should realize IClassFactory in my COM to instantiate not singleton? I've made COM with master in VC 2010 with ATL support. And I have a trouble where and how to realize IClassFactory.

Answer 1

You need to implement IUnknown, IClassFactory. Depending on what you're doing you may want to implement IDispatch and IErrorInfo as well. It's quite involved so I won't go into the details here. The following three articles should cover pretty much everything that you are after:

1. Step by Step COM Tutorial
2. Understanding Classic COM Interoperability With .NET Applications
3. Fundamentals of ATL COM Objects