function Big52Utf8(const S: string): UTF8String;
var
Len: Integer;
WS: WideString;
begin
Len := Length(S);
if Len = 0 then
Result := ''
else begin
SetLength(WS, Len);
Len := MultiByteToWideChar(950, 0, PChar(S), Len, PWideChar(WS), Len);
SetLength(WS, Len);
Result := UTF8Encode(WS);
end;
end;