c++/cli pass (managed) delegate to unmanaged code
- by Ron Klein
How do I pass a function pointer from managed C++ (C++/CLI) to an unmanaged method? I read a few articles, like this one from MSDN, but it describes two different assemblies, while I want only one.
Here is my code:
1) Header (MyInterop.ManagedCppLib.h):
#pragma once
using namespace System;
namespace MyInterop { namespace ManagedCppLib {
public ref class MyManagedClass
{
public:
void DoSomething();
};
}}
2) CPP Code (MyInterop.ManagedCppLib.cpp)
#include "stdafx.h"
#include "MyInterop.ManagedCppLib.h"
#pragma unmanaged
void UnmanagedMethod(int a, int b, void (*sum)(const int))
{
int result = a + b;
sum(result);
}
#pragma managed
void MyInterop::ManagedCppLib::MyManagedClass::DoSomething()
{
System::Console::WriteLine("hello from managed C++");
UnmanagedMethod(3, 7, /* ANY IDEA??? */);
}
I tried creating my managed delegate and then I tried to use Marshal::GetFunctionPointerForDelegate method, but I couldn't compile.