C++ dll中显示非模态对话框

1 通过window桌面向导创建一个DLL,添加对话框，对应的类分别为CPLCDlg和CEFEMDlg在dll对应的cpp里面添加如下代码

extern "C" __declspec(dllexport) void ShowPLC()
{
	AFX_MANAGE_STATE(AfxGetStaticModuleState());
	CPLCDlg plcDlg;
	plcDlg.Create(IDD_DLG_PLC, NULL);
	plcDlg.ShowWindow(SW_SHOW);
	MSG msg;
	while (GetMessage(&msg, NULL, 0, 0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

}

extern "C" __declspec(dllexport) void ShowEFEM()
{
	AFX_MANAGE_STATE(AfxGetStaticModuleState());
	CEFEMDlg efemDlg;
	efemDlg.Create(IDD_DLG_EFEM, NULL);
	efemDlg.ShowWindow(SW_SHOW);
	MSG msg;
	while (GetMessage(&msg, NULL, 0, 0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}
}

2 添加两个对话框类的WM_CLOSE消息处理函数来结束上面的消息循环

void CPLCDlg::OnClose()
{
	// TODO: 在此添加消息处理程序代码和/或调用默认值
	PostQuitMessage(0);
	CDialogEx::OnClose();
}

void CEFEMDlg::OnClose()
{
	// TODO: 在此添加消息处理程序代码和/或调用默认值
	PostQuitMessage(0);

	CDialogEx::OnClose();
}

3 主对话框菜单处理事件

void CNanoViewView::OnToolPlc()
{
	typedef void (WINAPI* TESTDLL)();
	HINSTANCE hmod;
	hmod = ::LoadLibrary(_T("ZASCtrlLib.dll"));
	if (hmod == NULL) { AfxMessageBox(_T("Fail")); }
	TESTDLL lpproc;
	lpproc = (TESTDLL)GetProcAddress(hmod, "ShowPLC");
	if (lpproc != (TESTDLL)NULL)
		(*lpproc)();
	FreeLibrary(hmod);
	
}


void CNanoViewView::OnToolEfem()
{
	typedef void (WINAPI* TESTDLL)();
	HINSTANCE hmod;
	hmod = ::LoadLibrary(_T("ZASCtrlLib.dll"));
	if (hmod == NULL) { AfxMessageBox(_T("Fail")); }
	TESTDLL lpproc;
	lpproc = (TESTDLL)GetProcAddress(hmod, "ShowEFEM");
	if (lpproc != (TESTDLL)NULL)
		(*lpproc)();
	FreeLibrary(hmod);
}