SynEdit, quelques trucs et astuces

procedure TUnicodeStrings.LoadFromStream(Stream: TStream);
// usual loader routine, but enhanced to handle byte order marks in stream
var
  Size,
  BytesRead: Integer;
  ByteOrderMask: array[0..5] of Byte; // BOM size is max 5 bytes (cf: wikipedia)
                                      // but it is easier to implement with a multiple of 2
  Loaded: Boolean;
  SW: UnicodeString;
  SA: AnsiString;
begin
  BeginUpdate;
  try
    Loaded := False;

    Size := Stream.Size - Stream.Position;
    BytesRead := Stream.Read(ByteOrderMask[0], SizeOf(ByteOrderMask));

    // UTF16 LSB = Unicode LSB/LE
    if (BytesRead >= 2) and (ByteOrderMask[0] = UTF16BOMLE[0])
      and (ByteOrderMask[1] = UTF16BOMLE[1]) then
    begin
      FSaveFormat := sfUTF16LSB;
      SetLength(SW, (Size - 2) div SizeOf(WideChar));
      Assert((Size and 1) <> 1, 'Number of chars must be a multiple of 2');
      if BytesRead > 2 then
      begin
        System.Move(ByteOrderMask[2], SW[1], BytesRead - 2); // max 4 bytes = 2 widechars
        if Size > BytesRead then
          // first 2 chars (maximum) were copied by System.Move
          Stream.Read(SW[3], Size - BytesRead);
      end;
      SetTextStr(SW);
      Loaded := True;
    end;

    // UTF16 MSB = Unicode MSB/BE
    if (BytesRead >= 2) and (ByteOrderMask[0] = UTF16BOMBE[0])
      and (ByteOrderMask[1] = UTF16BOMBE[1]) then
    begin
      FSaveFormat := sfUTF16MSB;
      SetLength(SW, (Size - 2) div SizeOf(WideChar));
      Assert((Size and 1) <> 1, 'Number of chars must be a multiple of 2');
      if BytesRead > 2 then
      begin
        System.Move(ByteOrderMask[2], SW[1] ,BytesRead - 2); // max 4 bytes = 2 widechars
        if Size > BytesRead then
          // first 2 chars (maximum) were copied by System.Move
          Stream.Read(SW[3], Size - BytesRead);
        StrSwapByteOrder(PWideChar(SW));
      end;
      SetTextStr(SW);
      Loaded := True;
    end;

    // UTF8
    if (BytesRead >= 3) and (ByteOrderMask[0] = UTF8BOM[0])
      and (ByteOrderMask[1] = UTF8BOM[1]) and (ByteOrderMask[2] = UTF8BOM[2]) then
    begin
      FSaveFormat := sfUTF8;
      SetLength(SA, (Size - 3) div SizeOf(AnsiChar));
      if BytesRead > 3 then
      begin
        System.Move(ByteOrderMask[3], SA[1], BytesRead - 3); // max 3 bytes = 3 chars
        if Size > BytesRead then
          // first 3 chars were copied by System.Move
          Stream.Read(SA[4], Size - BytesRead);
        SW := UTF8Decode(SA);
      end;
      SetTextStr(SW);
      Loaded := True;
    end;
    
    
    // UTF8 no-BOM or Ansi ----- Bug fixed, not origin of SynEdit -----
    if not Loaded then
    begin
      FSaveFormat := sfAnsi;
      SetLength(SA, Size div SizeOf(AnsiChar));
      if BytesRead > 0 then
      begin
        System.Move(ByteOrderMask[0], SA[1], BytesRead); // max 6 bytes = 6 chars
        if Size > BytesRead then
          Stream.Read(SA[7], Size - BytesRead); // first 6 chars were copied by System.Move
        SW := UTF8Decode(SA);
        if SW <> '' then begin   //UTF8 no-BOM
          FSaveFormat := sfUTF8;
          SetTextStr(SW);
          Loaded := True;
        end;
      end;
      if not Loaded then        //Ansi
        SetTextStr(SA);
    end;
    

    // default case (Ansi)    ----- Replaced -----
    {if not Loaded then
    begin
      FSaveFormat := sfAnsi;
      SetLength(SA, Size div SizeOf(AnsiChar));
      if BytesRead > 0 then
      begin
        System.Move(ByteOrderMask[0], SA[1], BytesRead); // max 6 bytes = 6 chars
        if Size > BytesRead then
          Stream.Read(SA[7], Size - BytesRead); // first 6 chars were copied by System.Move
      end;
      SetTextStr(SA);
    end; }                  
  finally
    EndUpdate;
  end;
end;

function TSynHTMLSyn.IsIdentChar(AChar: WideChar): Boolean;
begin
  case AChar of
    '_', '/', '0'..'9', 'A'..'Z', 'a'..'z',
    'À'..'Ö', 'Ù'..'Ý', 'à'..'ö', 'ù'..'ý', 'ÿ', 'ƒ': //Christian Feron 08/05/2016
      Result := True;
    else
      Result := False;
  end;
end;

procedure TForm1.GetFileEncoding(aFileName: String);
var
  aEncoding : TSynEncoding;
  aBOM : Boolean;
begin
 aEncoding := GetEncoding(aFileName, aBOM);//Identifies file encoding

 case aSynEncoding of
   seAnsi : Label1.Caption := 'Ansi';
   seUTF8 : begin
              if not aBOM then Label1.Caption := 'UTF8';
              if ABOM then Label1.Caption := 'UTF8Bom';
            end;
   seUTF16LE : Label1.Caption := 'LittleEndian';
   seUTF16BE : Label1.Caption := 'BigEndian';
 end;//End case...
end;

procedure TMainForm.InitMultiHighlighters;
begin
// HTML complex
 with SynMultiSyn1 do begin //----- Multi-Highlighters ----------------------
  DefaultHighlighter := SynHTMLSyn1;
  DefaultLanguageName:= 'HTML complex';
  DefaultFilter      := 'HTML complex (*.html; *.htm)|*.html; *.htm';
  with Schemes do begin
    Add.Index:= 0; //----- Javascript -----
    with Items[0] do begin
      SchemeName := 'Sch_Javascript';
      Highlighter := SynJScriptSyn1;
      StartExpr  := '<script';
      EndExpr    := '</script>';
      with MarkerAttri do begin
        Background := $00CDEBFF;//PeachPuff
        Foreground := clNavy;
      end;
    end;//End with Items[0]...
    Add.Index:= 1; //----- CSS -----
    with Items[1] do begin
      SchemeName := 'Sch_CSS';
      Highlighter := SynCssSyn1;
      StartExpr  := '<style';
      EndExpr    := '</style>';
      with MarkerAttri do begin
        Background := $00CDEBFF;//PeachPuff
        Foreground := clNavy;
      end;
    end;//End with Items[1]...
    
  end;//End with Schemes...
 end;//End with SynMultiSyn1...
end;