Marshalling const std::string parameters

Asked Mar 02 '22 at 07:16

Active Mar 02 '22 at 07:31

Viewed 163 times

When I try to import the function

extern __declspec(dllexport)  void SomeNativeFunction(const std::string param1, const std::string param2);

defined and declared in SomeNative.Dll into a .NET console application using

class Program
{
        [DllImport("SomeNative", CallingConvention = CallingConvention.Cdecl)]
        extern static void SomeNativeFuntion(string param1, string param2);
        static void Main(string[] args)
        {   
            StartEventHandling("param1", "param2");
        }
}

I get the error

System.AccessViolationException' occurred in ManagedS7DosEventManagerClient.dll Attempted to read or write protected memory. This is often an indication that other memory is corrupt.

Which is probably an indication, that I need to marshal the parameters correctly.

This overview of default marshalings for strings unfortunately doesn't say anything about marshaling of standard library strings.

edited Mar 02 '22 at 07:27

asked Mar 02 '22 at 07:16

Oblomov

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What have you tried so far? – user743414 Mar 02 '22 at 07:20
You can't marshal a `std::string`, you need to do something different – Alan Birtles Mar 02 '22 at 07:26
i.e. change the interface of the unmanaged dll? – Oblomov Mar 02 '22 at 07:28
That's certainly the easiest option – Alan Birtles Mar 02 '22 at 07:32

Marshalling const std::string parameters

0 Answers0