txt

procedure TForm1.Button1Click(Sender: TObject);
var
encriptLista:TStrings;
idx,i,Tamanho, codasc, key, calc:integer;
linha:String;
temp : Char;
begin
  encriptLista:=TStringList.Create;
  key := strtoint(edit1.Text);
  try
    encriptlista.LoadFromFile(´C:\original.txt´);
    for idx:= 0 to encriptLista.Count - 1 do
      begin
      Linha:=encriptlista.Strings[idx];
      tamanho:=length(linha);
        for i:=1 to tamanho do
        begin
        calc := key mod 256;
        codasc := ord(linha[i]);
        calc := calc + codasc;
        temp := Chr(calc);
        Linha[i]:=temp;
        end;
        encriptlista.Strings[idx]:=Linha
      end;
    encriptLista.SaveToFile(´C:\encript.txt´);
  finally
    encriptLista.Free;
    end;

end;
procedure TForm1.Button2Click(Sender: TObject);
var
decriptLista:TStrings;
didx,di,dTamanho, dcodasc, dkey, dcalc:integer;
dlinha:String;
dtemp : Char;
begin
  decriptLista:=TStringList.Create;
  try
    decriptlista.LoadFromFile(´C:\encript.txt´);
    dkey := strtoint(edit1.Text);
    for didx:= 0 to decriptLista.Count - 1 do
      begin
      dLinha:=decriptlista.Strings[didx];
      dtamanho:=length(dlinha);
        for di:=1 to dtamanho do
        begin
        dcalc := dkey mod 256;
        dcodasc := ord(dlinha[di]);
        dcalc := dcodasc - dcalc;
        dtemp := Chr(dcalc);
        dLinha[di]:=dtemp;
        end;
        decriptlista.Strings[didx]:=dLinha
      end;
    decriptLista.SaveToFile(´C:\decript.txt´);
  finally
    decriptLista.Free;
    end;
end;