encoding - Save INI file in UTF-8 rather than ANSI in Inno Setup

Question

I'm starting to use Inno Setup, and I have some problems with my INI file encoding.
I want to save user input in the INI file, and this input can contain accents.

I use Inno Setup Unicode, my setupScript.iss is UTF-8 encoded, and here is my code (a part) :

[INI]
Filename: "{app}wwwconfconfig.ini"; Section: "Settings"; Key: "ca.plafondAnnuel"; String: "{code:GetUser|Plafond}"
Filename: "{app}wwwconfconfig.ini"; Section: "Settings"; Key: "app.siren"; String: "{code:GetUser|Siren}"
Filename: "{app}wwwconfconfig.ini"; Section: "Settings"; Key: "app.adresse"; String: "{code:GetUser|Adresse}"


[Code]
var
  UserPage: TInputQueryWizardPage;
  ExamplePage : TInputOptionWizardPage;
  ImmatriculationPage : TInputOptionWizardPage;
  FakeElemIndex: Integer;
  FakeElem: TCustomEdit;
  AdresseTextarea: TNewMemo;

procedure InitializeWizard;
begin
  UserPage := CreateInputQueryPage(wpWelcome,
    'Configuration de l''application', '',
    'Configurez ici votre application. Une fois installée, vous pourrez modifier ces valeurs.');

  UserPage.Add('Siren :', False);
  UserPage.Add('Plafond annuel (utilisé par les auto-entreprises, mettre 0 si vous ne souhaitez pas plafonner votre chiffre d''affaire.):', False);

  FakeElemIndex := UserPage.Add('Votre adresse complète (telle qu''elle s''affichera sur les devis et factures, avec nom complet):', False);
  FakeElem  := UserPage.Edits[FakeElemIndex];

  AdresseTextarea := TNewMemo.Create(WizardForm);
  AdresseTextarea.Parent := FakeElem.Parent;
  AdresseTextarea.SetBounds(FakeElem.Left, FakeElem.Top, FakeElem.Width, ScaleY(50));

  // Hide the original single-line edit
  FakeElem.Visible := False;
end; 

function GetUser(Param: String): String;
begin
  if Param = 'Adresse' then
    Result := AdresseTextarea.Text
  else if Param = 'Siren' then
    Result := UserPage.Values[0]
  else if Param = 'Plafond' then
    Result := UserPage.Values[1];
end;

The value returned by getUser|Adresse in the [INI] part is not UTF-8 encoded: I open the INI file with Notepad++ and I see the file is UTF-8 encoded. But the value adresse is ANSI encoded (If I change the encoding of the file to ANSI, this value is readable)

Someone can help me understand how can I save this user input in UTF-8 ?

Thanks a lot !

Answer 1

The INI functions of Inno Setup ([INI] section and SetIni* functions) use internally the Windows API function WritePrivateProfileString.

This function does not support UTF-8 at all. All it supports is the ANSI encoding and UTF-16.
See How to read/write Chinese/Japanese characters from/to INI files?

So it's even questionable whether the target application will be able to read UTF-8-encoded INI file, if it relies on the Windows API function to read it.

---

Anyway, if you need the UTF-8, you would have to format the entries to INI format yourself and use SaveStringsToUTF8File function to write it.

---

The last option is to hack it by using the system call WritePrivateProfileString to write seemingly ANSI-encoded string, which will be in fact UTF-8-encoded.

For that you need to convert the string to UTF-8 in your code. You can use WideCharToMultiByte for that.

function WideCharToMultiByte(CodePage: UINT; dwFlags: DWORD;
  lpWideCharStr: string; cchWideChar: Integer; lpMultiByteStr: AnsiString;
  cchMultiByte: Integer; lpDefaultCharFake: Integer;
  lpUsedDefaultCharFake: Integer): Integer;
  external '[email protected] stdcall';

const
  CP_UTF8 = 65001;

function GetStringAsUtf8(S: string): AnsiString;
var
  Len: Integer;
begin
  Len := WideCharToMultiByte(CP_UTF8, 0, S, Length(S), Result, 0, 0, 0);
  SetLength(Result, Len);
  WideCharToMultiByte(CP_UTF8, 0, S, Length(S), Result, Len, 0, 0);
end;

function WritePrivateProfileString(
  lpAppName, lpKeyName, lpString, lpFileName: AnsiString): Integer;
  external '[email protected] stdcall';

procedure CurStepChanged(CurStep: TSetupStep);
var
  IniFileName: string;
begin
  if CurStep = ssInstall then
  begin
    Log('Writting INI file');
    if not ForceDirectories(ExpandConstant('{app}wwwconf')) then
    begin
      MsgBox('Error creating directory for INI file', mbError, MB_OK);
    end
      else
    begin
      IniFileName := ExpandConstant('{app}wwwconfconfig.ini');
      if (WritePrivateProfileString(
            'Settings', 'ca.plafondAnnuel', GetStringAsUtf8(GetUser('Plafond')),
            IniFileName) = 0) or
         (WritePrivateProfileString(
            'Settings', 'app.siren', GetStringAsUtf8(GetUser('Siren')),
            IniFileName) = 0) or
         (WritePrivateProfileString(
            'Settings', 'app.adresse', GetStringAsUtf8(GetUser('Adresse')),
            IniFileName) = 0) then
      begin
        MsgBox('Error writting the INI file', mbError, MB_OK);
      end;
    end;
  end;
end;