delphi UTF-8

 //Utf8存、取
procedure TForm1.Button1Click(Sender: TObject);
var
  S: string;
begin
//存
  with TMemoryStream.Create do try
    S := #$EF#$BB#$BF;
    Write(S[1], Length(S));
    S := AnsiToUtf8(Memo1.Text);
    Write(S[1], Length(S));
    Position := 0;
    SaveToFile('c:\temp\temp.txt');
  finally
    Free;
  end;
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  S: string;
begin
  //取
  if not FileExists('c:\temp\temp.txt') then Exit;
  with TMemoryStream.Create do try
    LoadFromFile('c:\temp\temp.txt');
    SetLength(S, Size);
    Read(S[1], Length(S));
    if Copy(S, 1, 3) <> #$EF#$BB#$BF then Exit;
    Memo2.Text := Utf8ToAnsi(Copy(S, 4, MaxInt));
  finally
    Free;
  end;
end;

http://hi.baidu.com/sail2000/blog/item/0a8cd52a6537a52dd42af180.html