read and write .ini file in MFC

Sometimes we need to configure the controls on the dialog based on the .ini and we may also need to save the final control values on the dialog to the same file in MFC, we can do that like this:

user.ini
[initialize]                   ;section name
m_listbox=0               ;key and int value       
name=zhiguang          ;key and string value


(1) example to initialize the controls on the dialog

BOOL CModalDlg::OnInitDialog() // read values from the .ini file
{
  
  CDialog::OnInitDialog();
  CString  iniFilePath;
  iniFilePath=".//ini//user.ini";
  // read ini for listbox
  int  list_pos;  
  list_pos=GetPrivateProfileInt("initialize","m_listbox",0,iniFilePath);
  m_listbox.AddString(_T("MIT"));
  m_listbox.AddString(_T("I.PAC"));
  m_listbox.AddString(_T("CASEM"));
  m_listbox.AddString(_T("Genric Power"));
  m_listbox.SetCurSel(list_pos);
  
  // read ini for edit
  CString  str_edit;  
  GetPrivateProfileString("initialize","IDC_EDIT1","",str_edit.GetBuffer(MAX_PATH),MAX_PATH,iniFilePath);
  SetDlgItemText(IDC_EDIT1, str_edit);

  // read ini for checkbox
  int  check_val;  
  check_val=GetPrivateProfileInt("initialize","m_check",0,iniFilePath);
  m_check.SetCheck(check_val);
  
  // read ini for radio
  int  radio_val;  
  radio_val=GetPrivateProfileInt("initialize","IDC_RADIO1",0,iniFilePath);
  if(radio_val==1)
  ((CButton *)GetDlgItem(IDC_RADIO1))->SetCheck(TRUE);
  else
  ((CButton *)GetDlgItem(IDC_RADIO2))->SetCheck(TRUE);

  return TRUE;
}

(2) example to update the control values on the dialog back to the same .ini file.

void CModalDlg::OnBnClickedOk() //save the values to the .ini file
{
 CString  iniFilePath;
    iniFilePath=".//ini//user.ini";

 //write ini for listbox
 int list_pos=m_listbox.GetCurSel();
 CString str_pos;
 str_pos.Format("%d",list_pos);
 WritePrivateProfileString("initialize","m_listbox",str_pos,iniFilePath);

 //write ini for editbox
 CString str_edit;
 GetDlgItemText(IDC_EDIT1, str_edit);
 WritePrivateProfileString("initialize","IDC_EDIT1",str_edit,iniFilePath);

   // read ini for checkbox
    int  check_val;  
    check_val=m_check.GetCheck();
 CString str_check;
 str_check.Format("%d",check_val);
 WritePrivateProfileString("initialize","m_check",str_check,iniFilePath);

   // read ini for radio button
    int  radio_val;  
    radio_val=((CButton *)GetDlgItem(IDC_RADIO1))->GetCheck();
 CString str_radio;
 str_radio.Format("%d",radio_val);
 WritePrivateProfileString("initialize","IDC_RADIO1",str_radio,iniFilePath);

 OnOK();
}

To read the file, we have  GetPrivateProfileString and GetPrivateProfileInt for String and Int values, to write the file , we only have WritePrivateProfileString, so we should convert the format of the value into CString first before writing