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I keep getting a System.EntryPointNotFoundException error when I try to call this function from a C++ DLL.

I'm using VS 2015 and these two projects are in the same solution. The C# project also references the C++ project.

Header file for DLL:

// MathLibrary.h - Contains declaration of Function class
#pragma once

#ifdef MATHLIBRARY_EXPORTS
#define MATHLIBRARY_API __declspec(dllexport) 
#else
#define MATHLIBRARY_API __declspec(dllimport) 
#endif


namespace MathLibrary {
    // This class is exported from the MathLibrary.dll

        class Functions {

        public:
            // Returns a + b
            static MATHLIBRARY_API double Add(double a, double b);

            // Returns a * b
            static MATHLIBRARY_API double Multiply(double a, double b);

            // Returns a + (a * b)
            static MATHLIBRARY_API double AddMultiply(double a, double b);
        };


}

Class file for DLL:

// MathLibrary.cpp : Defines the exported functions for the DLL application.
// Compile by using: cl /EHsc /DMATHLIBRARY_EXPORTS /LD MathLibrary.cpp

#include "stdafx.h"
#include "MathLibrary.h"

extern "C" {

    namespace MathLibrary {

        double Functions::Add(double a, double b) {
            return a + b;
        }

        double Functions::Multiply(double a, double b) {
            return a * b;
        }

        double Functions::AddMultiply(double a, double b) {
            return a + (a * b);
        }
    }
}

C# class I try to call the functions from:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Runtime.InteropServices;

namespace ConsoleApplication1
{
    class Program
    {

        [DllImport("K:\\C++\\MathLibraryAndClient\\Debug\\MathLibrary.dll")]
        public static extern double Add(double a, double b);

        static void Main(string[] args) {



            double a; double b;
            a = Console.Read();
            b = Console.Read();

            Add(a, b);
        }
    }
}

Thank you

ktfjulien
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    You'll have to use the Entrypoint property, the C++ function name is not "Add". Use the linker's .map file or run Dumpbin.exe /exports on the DLL to see the real names. Google "c++ name mangling" to learn more about it. – Hans Passant May 24 '16 at 17:29
  • Possible duplicate of [EntryPointNotFoundException when binding C++ dll in C#](https://stackoverflow.com/questions/12892271/entrypointnotfoundexception-when-binding-c-dll-in-c-sharp) – STF Jul 30 '17 at 04:38

0 Answers0