一种简单的字符串加密和解密算法

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

const
  XorKey:array[0..7] of Byte=($B2,$09,$AA,$55,$93,$6D,$84,$47);
type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Edit1: TEdit;
    Edit2: TEdit;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    function Encrypt(Str: string): string;
    function Decrypt(Str: string): string;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}



function TForm1.Encrypt(Str: string): string;//加密算法
var
  i,j:Integer;
begin
  Result := '';
  j := 0;
  for i := 1 to Length(Str) do
  begin
    Result := Result + IntToHex(Byte(Str[i]) xor XorKey[j],2);
    j := (j + 1) mod 8;
  end;
end;

function TForm1.Decrypt(Str: string): string;//解密算法
var
  i,j:Integer;
begin
  Result := '';
  j := 0;
  for i := 1 to Length(Str) div 2 do
  begin
    Result := Result + Char(StrToInt('$'+Copy(Str,i*2-1,2)) xor XorKey[j]);
    j := (j + 1) mod 8;
  end;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
  Edit2.Text :=Encrypt(Edit1.Text);
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  Edit1.Text := Decrypt(Edit2.Text);
end;

end.