That is an interesting question. I don't think you can directly, but Gary would have to weigh in on that. I only recently started to lightly dabble in C++, and here is an example of passing a string from a VA C# inline function to a 32-bit C++ library (bear in mind that C++ is quite foreign to me):
VA C# Inline Function
Referenced Assemblies: System.dll
using System;
using System.Text;
using System.Runtime.InteropServices;
public class VAInline
{
const string path = @"YourPathHere\MyLibary.dll"; // x86 library
public void main()
{
string str = "Hello World!";
StringBuilder sb = new StringBuilder(str, str.Length);
SendStringToPapyrus(sb);
}
[DllImport(path, CharSet = CharSet.Unicode, CallingConvention = CallingConvention.Cdecl)]
extern static void SendStringToCpp([MarshalAs(UnmanagedType.LPWStr)] StringBuilder str);
}
// References:
// http://www.cplusplus.com/doc/tutorial/files/
// https://manski.net/2012/05/pinvoke-tutorial-basics-part-1/
// https://social.msdn.microsoft.com/Forums/vstudio/en-US/0e808314-8888-4320-af94-dd0ffbb8ecfd/passing-c-stringbuilder-array-to-c-dll?forum=csharpgeneral
C++ Header (MyClass.h)
#pragma once
extern "C"
{
__declspec(dllexport) void SendStringToCpp(wchar_t* strIn);
}
C++ Declaration File (MyClass.cpp)
#pragma once
#include "MyClass.h"
#include <fstream>
#include <string>
using namespace std;
// Function for outputting a string to a text file
__declspec(dllexport) void SendStringToCpp(wchar_t* strIn)
{
wstring ws(strIn);
string MyString(ws.begin(), ws.end());
string FileName = "my_file.txt";
ofstream myfile;
myfile.open(FileName);
myfile << MyString;
myfile.close();
}
This will output the C# 'str' of "Hello World!" to a text file in VA's root directory. You can use this methodology to pass strings to your C++ library and with some additional massaging also pass other types.