Consume C#.NET COM Component in C++ [duplicate]

Here is the answer of this situation from my side:

Referring a C++ COM component is easy in .NET; all we have to do is to

• register (regsvr32 )
• Add a reference to the COM dll in the Visual Studio Solution
• An Interop file will be created in the bin directory of .NET project and we are done

But the reverse is not as simple as above.
So this time I have come up with Steps we need to follow in order to refer a COM visible .NET dll in C++ code.

• Register the COM Visible .NET assambly with regasm like this:
  regasm <dll_name_with_full_path> /tlb
  e.g.

  regasm "C:\SampleProject\bin\Release\Atreya.Anugrah.ComVisibleComponent.dll" /tlb
  

• Refer .NET component in .h file like this:
  #import "<generated_tlb_name_with_full_path>" named_guids raw_interfaces_only
  e.g.

  #import "C:\SampleProject\bin\Release\Atreya.Anugrah.ComVisibleComponent.tlb"  named_guids raw_interfaces_only
  

• Create a class in .h file, and declare member variable like this:
  ComVisibleComponent::* memberVariablePointer;
  e.g.

  Atreya_Anugrah_ComVisibleComponent::IMyInterface* m_pIMyInterface;
  

• Now, Initialize the declared member variable pointer in .cpp file like this:

  hr = CoCreateInstance( 
  __uuidof(Atreya_Anugrah_ComVisibleComponent::<Name_of_CoClass_Implementing_Interface>), // COM class id 
  NULL, // Outer unknown
  CLSCTX_ALL, // Server INFO 
  Atreya_Anugrah_ComVisibleComponent::IID_<Name_of_Interface>, // interface id
  (void**) &m_pIMyInterface);  // Returned Interface                                                                                                                   
  
  if (FAILED(hr))
  {
  _com_error e(hr);
  strErrorMsg.Format("Error: Unable to create COM Visible .NET component. hr = %d. Message = %s",hr, e.ErrorMessage());
  return hr;
  }
  
  //you are good to use your initialized pointer here :)   
  m_pIMyInterface->foo()
  

P.S. This post does not explain that how can we make our .NET component as COM visible. Please refer other post/article for that as it is quite simple activity.

Namaste! (Greetings)
Anugrah Atreya