//StrToByte函数
function StrToByte(Str : string):string;
var
  i : integer;
  temp : string;
begin
  for i := 1 to Length(Str) do
  begin
    temp := temp + CharToByte(byte(Str[i]));
  end;
  Result := Temp;
end;

//CharToByte函数
function CharToByte(S : integer):string;
var
  temp : string;
begin
  while true do
  begin
    if S mod 2 = 0 then
    begin
     S := S div 2;
     temp := temp + '0';
     if S = 1 then
     begin
       temp := temp + '1';
       break;
     end;
    end
    else begin
     S := S div 2;
     temp := temp + '1';
     if S = 1 then
     begin
       temp := temp + '1';
       break;
     end;
    end;
  end;
  Temp := LeftStr((Temp + '00000000'),8);
  Result := Temp;
end;

        
        string StrToByte(string Str)
        {
            string result = string.Empty;

            byte[] bs = Encoding.UTF8.GetBytes(Str);
            foreach (byte b in bs)
            {
                //将b转成二进制
                string tmp = Convert.ToString(b, 2);
                //不够8位左边补0
                tmp = tmp.PadLeft(8, '0');
                char[] cs = tmp.ToCharArray();
                //将所有元素进行倒序
                Array.Reverse(cs);
                tmp = new string(cs);
                result += tmp;
            }
            return result;
        }

//DecryptString函数
function DecryptString(Str: String): String;
var
  i : integer;
  temp : string;
begin
  for i := 1 to length(Str) do   
  begin
    if i mod 2 = 0 then
    begin
      if Str[i] = '1' then
        Str[i] := '0'
      else
        Str[i] := '1';
    end;
  end;

  for i := 1 to length(Str) do
  begin
    if i mod 8 = 0 then
    begin
      temp := temp + ByteToChar(copy(Str,i-7,8));
    end;
  end;
  Result := temp;
end;

//ByteToChar函数
function ByteToChar(ByteStr : string):String;
var
  i : integer;
  IntVal : extended;// extended == c#:double
begin
  IntVal := 0;
  for i := 1 to length(ByteStr) do
  begin
    IntVal := IntVal + powerEx(2,i-1) * strtoint(ByteStr[i]);
  end;
  Result := Chr(strtoint(FloatToStr(IntVal)));
end;

//PowerEx函数
function PowerEx(x, y : extended) : extended;
begin
  result := exp(y*ln(x));
end;

        string DecryptString(string Str)
        {
            string result = string.Empty;
            char[] cs = Str.ToCharArray();
            for (int i = 0; i < cs.Length; i++)
            {
                if ((i + 1) % 2 == 0)
                {
                    if (cs[i] == '1')
                        cs[i] = '0';
                    else
                        cs[i] = '1';
                }
            }
            Str = new string(cs);
            for (int j = 0; j < Str.Length; j++)
            {
                if ((j + 1) % 8 == 0)
                {
                    result += ByteToChar(Str.Substring(j - 7, 8));
                }
            }
            return result;
        }
        string ByteToChar(string ByteStr)
        {
            double IntVal = 0;
            string result = string.Empty;

            for (int i = 0; i < ByteStr.Length; i++)
            {
                IntVal += PowerEx(2, i) * Convert.ToInt32(ByteStr[i].ToString());
            }
            return Convert.ToChar(Convert.ToInt32(IntVal.ToString())).ToString();
        }
        double PowerEx(double x, double y)
        {
            return Math.Exp(y * Math.Log(x, Math.E));
        }