Delphi Berlin 10.1 OS X app Decode Cyrillic for writing to hardDevice

Question

I have delphi application, I need to rewrite it for OS X. This app writes/reads data to/from HID-device.

I have issues when I'm trying to write string from mac.

Here is the line that I'm writing(from debugger on windows): 'Новый комплекс 1' and this works good. Meanwhile if copy this from debugger to somewhere it becomes 'Íîâûé êîìïëåêñ 1'. Device shows it as it was written, in cyrillic. And that's OK.

When I'm trying to repeat this steps on OS X, device shows unreadable symbols. But if I do hardcode 'Íîâûé êîìïëåêñ 1' from windows example it's OK again.

Give some hints.

How it on Windows

Some code:

 s:= 'Новый комлекс 1'

s:= AnsiToUtf8(ReplaceNull(s));

Here is ReplaceNULL:

function ReplaceNull(const Input: string): string;
var
Index: Integer;
Res: String;
begin
Res:= '';
for Index := 1 to Length(Input) do
begin
if Input[Index] = #0 then
  Res:= Res + #$12
else
  Res:= Res + Input[Index];
end;
 ReplaceNull:= Res;
end;

this string I put to Tstringlist and then save to file:

ProgsList.SaveToFile(Mwork.pathLibs+'stream.ini', TEncoding.UTF8);

Other program read this list and then writes to device:

Progs:= TStringList.Create();

Progs.LoadFromFile(****);

s:= UTF8ToAnsi(stringreplace(Progs.Strings[i], #$12, #0, [rfReplaceAll,   rfIgnoreCase]));

And then write it to device.

So the line which writes seems like this:

"'þ5'#0'ÿ'#$11'Новый комплекс 1'#0'T45/180;55;70;85;90;95;100;T45/180'#0'ÿ'"

On the Mac I successfully get the same string. But device can't show this in Cyrillic.

Answer 1

A Delphi string is encoded in UTF-16 on all platforms. There is no need to convert it, unless you are interacting with non-Unicode data outside of your app.

That being said, if you have a byte array that is encoded in a particular charset, you can convert it to another charset using Delphi's TEncoding.Convert() method. You can use the TEncoding.GetEncoding() method to get a TEncoding object for a particular charset (if different than the standard supported charsets - ANSI, ASCII, UTF-7, UTF-8, and UTF-16 - which have their own property getters in TEncoding).

var
  SrcEnc, DstEnc: TEncoding;
  SrcBytes, ConvertedBytes: TBytes;
begin
  SrcBytes := ...; // Cyrillic encoded bytes
  SrcEnc := TEncoding.GetEncoding('Cyrillic'); // or whatever the real name is...
  try
    DstEnc := TEncoding.GetEncoding('Windows-1251');
    try
      ConvertedBytes := TEncoding.Convert(SrcEnc, DstEnc, SrcBytes);
    finally
      DstEnc.Free;
    end;
  finally
    SrcEnc.Free;
  end;
  // use ConvertedBytes as needed...
end;

Update: To encode a Unicode string in a particular charset, simply call the TEncoding.GetBytes() method, eg:

s := 'Новый комлекс 1';
Enc := TEncoding.GetEncoding('Windows-1251');
try
  bytes := Enc.GetBytes(s);
finally
  Enc.Free;
end;

s := 'Новый комлекс 1';
bytes := TEncoding.UTF8.GetBytes(s);

You can use the TEncoding.GetString() to decode bytes in a particular charset back to a String, eg:

bytes := ...; // Windows-1251 encoded bytes
Enc := TEncoding.GetEncoding('Windows-1251');
try
  s := Enc.GetString(bytes);
finally
  Enc.Free;
end;

bytes := ...; // UTF-8 encoded bytes
s := TEncoding.UTF8.GetString(bytes);

Answer 2

The answer was next. Delphi Berlin 10.1 uses KOI8-R, and my device - cp1251. As i'd wanted to write russian symbols(Cyrillic) i've created table of matches for symbols from KOI8-R and cp1251.

So, i take string in KOI8-R make it in cp1251.

Simple code:

 Dict:=TDictionary<String,String>.Create;
 Dict.Add(#$439,#$E9);//'й'
 Dict.Add(#$44E,#$FE);//'ю'
 Dict.Add(#$430,#$E0);//'а'

....

function tkoitocp.getCP1251Code(str:string):string;
var i:integer; res,key,val:string;  pair:Tpair<String,String>;
begin
res:='';
for i:=1 to length(str) do
 begin
   if dict.ContainsKey(str[i]) then
   begin
      pair:= dict.ExtractPair(str[i]);

      res:=res+pair.Value;
      dict.Add(pair.Key,pair.Value);
   end
   else
   res:=res+str[i];
 end;
 Result:=res;

end;