Using the _CDECL calling convention in C# (changing compiler service)

//#include "Globals.h"
#include<string.h>
#ifdef __cplusplus
extern "C" {
#endif

typedef (__cdecl *fptr)(int a,int b);

int Sum(int a, int b)     
{
    return a+b;
}



int testfuncptr(int a, int b,fptr ptr)
{
	//fptr = &Sum;
	return ptr(a,b);
}


#ifdef __cplusplus
}
#endif