C / C++ / MFC

2 Errors:
a) Lambda does not not with static var, so I must to work wwith bind
b) I try to invoke functions of class from DLL, saved in unordered_map object and fall.If to invoke functions of class not from DLL it is work properly.
How can this problem be solved?


	file UnorderedMapFunctions.cpp
<pre lang="C++">#include <iostream>
#include <unordered_map>
#include <functional>
#include <windows.h>

#include "..\\Geometry\\Geometry.h"
using namespace std;

namespace NS
{
  class Math
  {
  public:
    int Sum(int x, int y) { return x + y; }
    int Sub(int x, int y) { return x - y; }
    int Mul(int x, int y) { return x * y; }
    int Div(int x, int y) { return x / y; }
  };
}
using namespace NS;

int main()
{
  unordered_map<string, function<int(int, int)>>* mydata = new unordered_map<string, function<int(int, int)>>;
  Math* m = new Math;
 
  // Using lambda functions to bind member functions
  (*mydata)["sum"] = [m](int x, int y) { return m->Sum(x, y); };
  (*mydata)["sub"] = [m](int x, int y) { return m->Sub(x, y); };
  (*mydata)["mul"] = [m](int x, int y) { return m->Mul(x, y); };
  (*mydata)["div"] = [m](int x, int y) { return m->Div(x, y); };
  /*
  //Geometry* g = new Geometry;
  (*mydata)["circle"] = [g](int x, int y) { return g->Circle(x, y); };
  (*mydata)["rectangle"] = [g](int x, int y) { return g->Rectangle(x, y); };
  */
  //==============================================================
  string fullname_dll = "Geometry";
  HINSTANCE hInst = LoadLibraryA(fullname_dll.c_str());
  if (hInst == nullptr)
  {
    cout << "Error: [FuncImport] wrong name " << fullname_dll.c_str() << endl;
    return false;
  }
  typedef void (CALLBACK* CreateInstanceFunc)(unordered_map<string, function<int(int, int)>>* mydata);
  string CreateFuncName = "CreateInstance"; 
  CreateInstanceFunc CreateInstance = (CreateInstanceFunc)GetProcAddress(hInst, CreateFuncName.c_str()); 
  if (CreateInstance == nullptr)
  {
    cout << "Error: wrong name " << fullname_dll << endl;
    FreeLibrary(hInst);
    return false;
  }
  CreateInstance(mydata);
  cout << "Imported " << fullname_dll.c_str();
  FreeLibrary(hInst);
  //==============================================================
  // Invoke by 'key' functions, saved in 'mydata'
  // it is right! 
  for (const auto& [k, v] : *mydata)
    std::cout << "Key: " << k << " Value: " << v(3, 5) << std::endl;
  //===================================
  auto it = mydata->find("circle");
  if (it != mydata->end())
   // Exception thrown: read access violation.
   // fault in functional.h line 920
   // it->second.vfptr = addr(??? ??? ??? ??? ???)
    cout << "\nKey: " << it->first << " Value: " << it->second(4, 2) << std::endl;
  else
    cout << "Error\n";
  //===================================

  delete m;
  delete mydata;
  return 0;
}

#pragma once
#include <iostream>
#include <unordered_map>
#include <functional>
#include <windows.h>

#ifdef GEOMETRY_EXPORTS
#define GEOMETRY_API __declspec(dllexport)
#else
#define GEOMETRY_API __declspec(dllimport)
#endif

using namespace std;
namespace NS
{
  class GEOMETRY_API Geometry
  {
  public:
    Geometry();
    int Circle(int x, int y);
    int Rectangle(int x, int y);
  };
  extern "C" void  GEOMETRY_API  CreateInstance(unordered_map<string, function<int(int, int)>>* mydata);
  extern "C" void  GEOMETRY_API  Cleanup();
}

#include "pch.h"
#include "Geometry.h"

namespace NS
{
   Geometry* geometryInstance;
  void CreateInstance(unordered_map<string, function<int(int, int)>>* mydata)
  {
    geometryInstance = new Geometry;
    // Can't capture a static variable in a lambda
    //(*mydata)["circle"] = [geometryInstance](int x, int y) { return geometryInstance->Circle(x, y); };
    //(*mydata)["rectangle"] = [geometryInstance](int x, int y) { return geometryInstance->Rectangle(x, y); };

    (*mydata)["circle"] = bind(&Geometry::Circle, geometryInstance, placeholders::_1, placeholders::_2);
    (*mydata)["rectangle"] = bind(&Geometry::Rectangle, geometryInstance, placeholders::_1, placeholders::_2);
  }
  Geometry::Geometry() {}
  int Geometry::Circle(int x, int y) { return 3.14 * x * x; }
  int Geometry::Rectangle(int x, int y) { return x * y; }
  void Cleanup()
  {
        delete geometryInstance;
        geometryInstance = nullptr;
  }
}

Prepare the following strings in advance as an array. Be sure to write everything in full-width characters.
"The difference between being 18 and 81. 18 years old is the one who drowns in love, 81 years old is the one who drowns in the bath. 18 years old is the one who runs down the road, and vice versa.
The person running is 81 years old. An 18-year-old has a fragile heart, and an 81-year-old has a fragile bone. I'm 18 years old and my heart can't stop pounding.
He is 81 years old and can't stop the plane. An 18-year-old can choke on love, and an 81-year-old can choke on rice cakes. I'm concerned about the deviation value
I am 18 years old, and I am 81 years old and concerned about my blood pressure and blood sugar levels. An 18-year-old who doesn't know anything yet, an 81-year-old who doesn't remember anything anymore.
An 18-year-old who is looking for himself, and an 81-year-old who is looking for everyone else. "
- Then have the user enter a search string. Search characters can be up to 10 characters.
・Then, have the user enter a replacement string. Replacement characters can be up to 10 characters.
- Perform a prefix match search on the above string and replace all hit strings.
- After replacing, output the result to the screen. If there are no conversion candidates, "Nothing to convert" is displayed.(if the searched string is in more than 1 place on the original string, the replacement will replace all of it)

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