How to catch unmanaged C++ exception in managed C++

Question

I am developing a thin managed C++ wrapper over a large unmanaged C++ library, and a large C# library. I need to catch errors originating in that large unmanaged C++ library, an

Answer 1

I use

#include 
#include 

using namespace System;
using namespace msclr::interop;

try
{
    ...
}

catch (const std::exception& e)
{
    throw gcnew Exception(marshal_as(e.what()));
}

catch (...)
{
    throw gcnew Exception("Unknown C++ exception");
}

You may want to put this into a pair of macros since they'll be used everywhere.

You can add a custom catch block with your Error class, but since it seems to derive from std::exception, the code I show you should be OK.

You could also want to catch more specifically std::invalid_argument and translate it into ArgumentException, etc. but I find this overkill.