procedure TForm1.btnUpClick(Sender :TObject);
begin
SynEdit1.Lines.Exchange(SynEdit1.CaretY-1, SynEdit1.CaretY-2 );
SynEdit1.CaretY := SynEdit1.CaretY - 1;
end;
procedure TForm1.btnDownClick(Sender :TObject);
begin
SynEdit1.Lines.Exchange(SynEdit1.CaretY-1, SynEdit1.CaretY );
SynEdit1.CaretY := SynEdit1.CaretY + 1;
end;