Changer sur le système la séparation décimale

Procedure SetDecimalSeparator(Ch:Char);
var
DefLCID : LCID;
Buffer : LPSTR;

begin
Application.UpdateFormatSettings := True;
StrPCopy(Buffer,Ch);
DefLCID := GetThreadLocale;
if SetLocaleInfo(DefLCID,LOCALE_SDecimal,Buffer) then begin
DecimalSeparator := strpas(Buffer)[1];
end;
Application.UpdateFormatSettings := False;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
SetDecimalSeparator('.');
end;