在工程名.h头文件中写public:

class CaccessimageApp : public CWinApp
{
public:
    _ConnectionPtr m_pConnection;
    CaccessimageApp();

// 重写
public:
    virtual BOOL InitInstance();
    virtual int ExitInstance();
// 实现

    DECLARE_MESSAGE_MAP()
};

class CaccessimageApp : public CWinApp

原文地址:https://www.cnblogs.com/wxl845235800/p/7384846.html