Как связать диалог IDD с обьектом mfc?

void CMyFrameWnd::OnFile_Open()
{
     TCHAR szFilters[]= _T("MyType Files (*.txt)|*.my|All Files (*.*)|*.*||");
     
   // Create an Open dialog; the default file name extension is ".my".
   CFileDialog fileDlg(TRUE, _T("txt"), _T("*.txt"),
       OFN_FILEMUSTEXIST | OFN_HIDEREADONLY, szFilters);
 
   // Display the file dialog. When user clicks OK, fileDlg.DoModal() 
   // returns IDOK.
   if(fileDlg.DoModal() == IDOK)
   {
      //вот прям тут я хочу его сделать видимым. Я в mfc новичек, тут другая планета :3
      CString pathName = fileDlg.GetPathName();
      CString fileName = fileDlg.GetFileTitle();
      CString s;
      SetWindowText(fileName);
   }
    
}

void CMyFrameWnd::OnFile_Open()
{
     TCHAR szFilters[]= _T("MyType Files (*.txt)|*.my|All Files (*.*)|*.*||");
     
   // Create an Open dialog; the default file name extension is ".my".
   CFileDialog fileDlg(TRUE, _T("txt"), _T("*.txt"),
      OFN_FILEMUSTEXIST | OFN_HIDEREADONLY, szFilters);
 
   // Display the file dialog. When user clicks OK, fileDlg.DoModal() 
   // returns IDOK.
   if(fileDlg.DoModal() == IDOK)
   {
      CString pathName = fileDlg.GetPathName();
      CStdioFile fOpen(pathName, CFile::modeRead);
      CC mydlg;
      mydlg.DoModal();
      char buff[10];
      CString s;
      CEdit *MyEdit;
      MyEdit = (CEdit*)GetDlgItem(IDC_EDIT1);
      MyEdit->Clear();
      while (fOpen.ReadString(s)) s+=buff;
      MyEdit->SetWindowTextA(s);
      // Implement opening and reading file in here.
      UpdateData(false);
      fOpen.Close();
      //Change the window's title to the opened file's title.
      CString fileName = fileDlg.GetFileTitle();
 
      SetWindowText(fileName);
   }
    //::MessageBox(NULL,"C", "File Open", MB_OK|MB_ICONEXCLAMATION);
}

class CC: public CDialog
{
public:
    CC(CWnd* pParent = NULL);
    enum {IDD  = IDD_DIALOG2};
    DECLARE_MESSAGE_MAP()
    afx_msg void OnEnChangeEdit1();
};
CC::CC(CWnd* pParent):CDialog(CC::IDD, pParent)
{
    
}

BEGIN_MESSAGE_MAP()  
END_MESSAGE_MAP()

if(fileDlg.DoModal() == IDOK)
   {
      CC mydlg;
      mydlg.DoModal();
      FILE* out;
      CString pathName = fileDlg.GetPathName();
      out=fopen(pathName,"r");
      char buff[10];
      CString str;
      CEdit *MyEdit;
      MyEdit = (CEdit*)GetDlgItem(IDC_EDIT1);
      MyEdit->Clear();
      while (fgets(buff,10,out)) str+=buff;
      MyEdit->SetWindowTextA(str);
      CString fileName = fileDlg.GetFileTitle();
      SetWindowText(fileName);
      
   }

{ ASSERT(::IsWindow(m_hWnd)); ::SendMessage(m_hWnd, WM_CLEAR, 0, 0); }