C++第四十三篇 -- VS2017创建控制台程序勾选MFC类库

用VS2017创建EXE带MFC类库方法

1. File --> New --> Project

2. Windows桌面向导

3. 勾选MFC类库

4. 创建成功

如果项目编译出错

1. 项目创建成功后编译报错界面

原因分析：缺少#include <afxwin.h>头文件。

解决方案：在#include "Project1.h"后面添加#include <afxwin.h>，编译通过。

如果上述方法不行，可参考下面解决方法，否则跳过以下内容。

原因分析：对比别人创建成功的项目，发现多了一个#include "framework.h"

解决方案：copy成功项目的framework.h头文件，并#include "framework.h"，另外framework.h头文件中引用了targetver.h头文件，因此，将targetver.h头文件也copy过来

2. 编译成功后的界面

3. framework.h

#pragma once

#include "targetver.h"
#include <stdio.h>
#include <tchar.h>
#define _ATL_CSTRING_EXPLICIT_CONSTRUCTORS      // 部分 CString 构造函数将是显式的
#define _AFX_NO_MFC_CONTROLS_IN_DIALOGS         // 移除对话框中的 MFC 控件支持

#ifndef VC_EXTRALEAN
#define VC_EXTRALEAN            // 从 Windows 头文件中排除极少使用的内容
#endif

#include <afx.h>
#include <afxwin.h>         // MFC 核心组件和标准组件
#include <afxext.h>         // MFC 扩展
#ifndef _AFX_NO_OLE_SUPPORT
#include <afxdtctl.h>           // MFC 对 Internet Explorer 4 公共控件的支持
#endif
#ifndef _AFX_NO_AFXCMN_SUPPORT
#include <afxcmn.h>                     // MFC 对 Windows 公共控件的支持
#endif // _AFX_NO_AFXCMN_SUPPORT

#include <iostream>

4. targetver.h

#pragma once

// // 包含 SDKDDKVer.h 可定义可用的最高版本的 Windows 平台。
// 如果希望为之前的 Windows 平台构建应用程序，在包含 SDKDDKVer.h 之前请先包含 WinSDKVer.h 并
// 将 _WIN32_WINNT 宏设置为想要支持的平台。
#include <SDKDDKVer.h>

这样就不会编译出错了。

EXE调用MFC窗口

1. 新建一个子窗口

2. 修改SubWin1.cpp中#include "stdafx.h"为#include "pch.h"并且注释掉#include "Project1.h"，然后添加#include "resource.h"如下

3. 在Project1.cpp中添加#include "SubWin1.h"，然后用以下语句调用SubWin窗口

    SubWin1 *chartdialog = new SubWin1;
    int ReturnValue = chartdialog->DoModal(); // Show the dialog
    printf("%d\n", ReturnValue);

Project1.cpp

// Project1.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include "pch.h"
#include "Project1.h"
#include <afxwin.h>
#include "win_test.h"
#include "SubWin1.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#endif

// The one and only application object

CWinApp theApp;

using namespace std;

void win_test_show() {
    //win_test *chartdialog = new win_test;
    //int ReturnValue = chartdialog->DoModal(); // Show the dialog
    //printf("%d\n", ReturnValue);

    SubWin1 *chartdialog = new SubWin1;
    int ReturnValue = chartdialog->DoModal(); // Show the dialog
    printf("%d\n", ReturnValue);
}

int call() {
    int nRetCode = 0;

    HMODULE hModule = ::GetModuleHandle(nullptr);

    if (hModule != nullptr)
    {
        // initialize MFC and print and error on failure
        if (!AfxWinInit(hModule, nullptr, ::GetCommandLine(), 0))
        {
            // TODO: code your application's behavior here.
            wprintf(L"Fatal Error: MFC initialization failed\n");
            nRetCode = 1;
        }
        else
        {
            // TODO: code your application's behavior here.
            win_test_show();
        }
    }
    else
    {
        // TODO: change error code to suit your needs
        wprintf(L"Fatal Error: GetModuleHandle failed\n");
        nRetCode = 1;
    }
    return nRetCode;
}

int main()
{
    int nRetCode = 0;

    call();

    return nRetCode;
}

可以看到窗口已经成功调用了

创建DLL带MFC类库方法

1. 新建一个Windows Desktop Wizard项目

2. 勾选MFC，新建DLL

3. 编译程序，编译成功。

4. 新建一个Win32程序用来测试Dll

5. 在Dll中新建一个MFC的窗口

6. Project2.cpp中调用它，修改Project.cpp如下

// Project2.cpp : Defines the exported functions for the DLL application.
//

#include "stdafx.h"
#include "Project2.h"
#include "SubWin1.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#endif

// The one and only application object

CWinApp theApp;

using namespace std;

int Function()
{
    int nRetCode = 0;

    HMODULE hModule = ::GetModuleHandle(nullptr);

    if (hModule != nullptr)
    {
        // initialize MFC and print and error on failure
        if (!AfxWinInit(hModule, nullptr, ::GetCommandLine(), 0))
        {
            // TODO: code your application's behavior here.
            wprintf(L"Fatal Error: MFC initialization failed\n");
            nRetCode = 1;
        }
        else
        {
            // TODO: code your application's behavior here.
            SubWin1 *chartdialog = new SubWin1;
            int ReturnValue = chartdialog->DoModal(); // Show the dialog
            printf("%d\n", ReturnValue);
        }
    }
    else
    {
        // TODO: change error code to suit your needs
        wprintf(L"Fatal Error: GetModuleHandle failed\n");
        nRetCode = 1;
    }

    return nRetCode;
}

7. 修改Project.h如下

// The following ifdef block is the standard way of creating macros which make exporting
// from a DLL simpler. All files within this DLL are compiled with the {0}_EXPORTS
// symbol defined on the command line. This symbol should not be defined on any project
// that uses this DLL. This way any other project whose source files include this file see
// {0}_API functions as being imported from a DLL, whereas this DLL sees symbols
// defined with this macro as being exported.
#ifdef __cplusplus
extern "C" {
#endif

#ifdef PROJECT2_EXPORTS
#define PROJECT2_API __declspec(dllexport)
#else
#define PROJECT2_API __declspec(dllimport)
#endif

// This class is exported from the dllxiu
    PROJECT2_API int Function();

#ifdef __cplusplus
}
#endif

8. 将SubWin1.cpp中添加头文件#include "resource.h"

// SubWin1.cpp : implementation file
//

#include "stdafx.h"
#include "Project2.h"
#include "SubWin1.h"
#include "afxdialogex.h"
#include "resource.h"

// SubWin1 dialog

IMPLEMENT_DYNAMIC(SubWin1, CDialog)

SubWin1::SubWin1(CWnd* pParent /*=nullptr*/)
    : CDialog(IDD_SubWin1, pParent)
{

}

SubWin1::~SubWin1()
{
}

void SubWin1::DoDataExchange(CDataExchange* pDX)
{
    CDialog::DoDataExchange(pDX);
}

BEGIN_MESSAGE_MAP(SubWin1, CDialog)
END_MESSAGE_MAP()

// SubWin1 message handlers

9. 编辑Test.cpp调用dll，本次采用的是静态加载DLL的方法，具体操作方法可以看前文。

// Test.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include "pch.h"
#include <iostream>
#include "../Project2/Project2.h"

int main()
{
    std::cout << "Hello World!\n";
    Function();
}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started:
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file

10. 执行结果如下

chartdialog->DoModal()的返回结果居然是-1，这里就是DLL调用MFC类和EXE调用MFC类的区别所在了。解决这个问题的关键就是要在调用窗口语句之前加上AFX_MANAGE_STATE(AfxGetStaticModuleState());这句话。

Project2.cpp

// Project2.cpp : Defines the exported functions for the DLL application.
//

#include "stdafx.h"
#include "Project2.h"
#include "SubWin1.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#endif

// The one and only application object

CWinApp theApp;

using namespace std;

int Function()
{
    int nRetCode = 0;

    HMODULE hModule = ::GetModuleHandle(nullptr);

    if (hModule != nullptr)
    {
        // initialize MFC and print and error on failure
        if (!AfxWinInit(hModule, nullptr, ::GetCommandLine(), 0))
        {
            // TODO: code your application's behavior here.
            wprintf(L"Fatal Error: MFC initialization failed\n");
            nRetCode = 1;
        }
        else
        {
            // TODO: code your application's behavior here.
            AFX_MANAGE_STATE(AfxGetStaticModuleState());
            SubWin1 *chartdialog = new SubWin1;
            int ReturnValue = chartdialog->DoModal(); // Show the dialog
            printf("%d\n", ReturnValue);
        }
    }
    else
    {
        // TODO: change error code to suit your needs
        wprintf(L"Fatal Error: GetModuleHandle failed\n");
        nRetCode = 1;
    }

    return nRetCode;
}

这样就可以成功的在DLL中调出窗口。