从网上整理的一些delphi字符串加密解密方法

function Encode(Str: string): string;var //加密  TmpChr: AnsiChar;  i, Len: integer;begin  Result := Str;  Len := Length(Result);  TmpChr := Result[1];  for i := 1 to Len - 1 do    Result[i] := Result[i + 1];  Result[Len] := TmpChr;end;
function Decode(Str: string): string;var //解密  TmpChr: AnsiChar;  i, Len: integer;begin  Result := Str;  Len := Length(Result);  TmpChr := Result[Len];  for i := Len downto 2 do    Result[i] := Result[i - 1];  Result[1] := TmpChr;end;
{异或 加密解密}const // 首先定义一个常量数组  XorKey: array[0..7] of Byte = ($B2, $91, $AA, $55, $93, $6D, $84, $47); //字符串加密用//数组的值可以自己改
function Enc(Str: string): string; //字符加密函數   這是用的一個異或加密var  i, j: Integer;begin  Result := '';  j := 0;  for i := 1 to Length(Str) do  begin    Result := Result + IntToHex(Byte(Str[i]) xor XorKey[j], 2);    j := (j + 1) mod 8;  end;end;
function Dec(Str: string): string; //字符解密函數var  i, j: Integer;begin  Result := '';  j := 0;  for i := 1 to Length(Str) div 2 do  begin    Result := Result + Char(StrToInt('$' + Copy(Str, i * 2 - 1, 2)) xor XorKey[j]);    j := (j + 1) mod 8;  end;end;
function Crypt(s: string; Key: Word;  const bEncrypt: boolean): string;const  SeedA = 787; ///   常量，你可以修改  SeedB = 787; ///   常量，你可以修改var  i: integer;  ps, pr: ^byte;begin  if bEncrypt then    s := s + #0;  SetLength(Result, Length(s));  ps := @s[1];  pr := @Result[1];  for i := 1 to length(s) do  begin    pr^ := ps^ xor (Key shr 8);    if bEncrypt then      Key := (pr^ + Key) * SeedA + SeedB    else      Key := (ps^ + Key) * SeedA + SeedB;    pr := pointer(integer(pr) + 1);    ps := pointer(integer(ps) + 1);  end;end;///////////////////function EncrypStr(Src, Key: string): string; //字符串加密函数//对字符串加密(Src:源 Key:密匙)var KeyLen: Integer;  KeyPos: Integer;  offset: Integer;  dest: string;  SrcPos: Integer;  SrcAsc: Integer;  Range: Integer;begin  KeyLen := Length(Key);  if KeyLen = 0 then key := 'delphi';  KeyPos := 0;  Range := 256;  Randomize;  offset := Random(Range);  dest := format('%1.2x', [offset]);  for SrcPos := 1 to Length(Src) do  begin    SrcAsc := (Ord(Src[SrcPos]) + offset) mod 255;    if KeyPos < KeyLen      then KeyPos := KeyPos + 1    else KeyPos := 1;    SrcAsc := SrcAsc xor Ord(Key[KeyPos]);    dest := dest + format('%1.2x', [SrcAsc]);    offset := SrcAsc;  end;  Result := Dest;end;
function UncrypStr(Src, Key: string): string; //字符串解密函数//对字符串解密(Src:源 Key:密匙)var KeyLen: Integer;  KeyPos: Integer;  offset: Integer;  dest: string;  SrcPos: Integer;  SrcAsc: Integer;  TmpSrcAsc: Integer;begin  KeyLen := Length(Key);  if KeyLen = 0 then key := 'delphi';  KeyPos := 0;  offset := StrToInt('$' + copy(src, 1, 2));  SrcPos := 3;  repeat    SrcAsc := StrToInt('$' + copy(src, SrcPos, 2));    if KeyPos < KeyLen      then KeyPos := KeyPos + 1    else KeyPos := 1;    TmpSrcAsc := SrcAsc xor Ord(Key[KeyPos]);    if TmpSrcAsc <= offset      then TmpSrcAsc := 255 + TmpSrcAsc - offset    else TmpSrcAsc := TmpSrcAsc - offset;    dest := dest + chr(TmpSrcAsc);    offset := srcAsc;    SrcPos := SrcPos + 2;  until SrcPos >= Length(Src);  Result := Dest;end;
//********************************************************//             加密解密 (利用异或运算)    （方式2）//********************************************************
function encryptstr(const s: string; skey: string): string; //加密var  i, j: integer;  hexS, hexskey, midS, tmpstr: string;  a, b, c: byte;begin  hexS := myStrtoHex(s);  hexskey := myStrtoHex(skey);  midS := hexS;  for i := 1 to (length(hexskey) div 2) do  begin    if i <> 1 then midS := tmpstr;    tmpstr := '';    for j := 1 to (length(midS) div 2) do    begin      a := strtoint('$' + midS[2 * j - 1] + midS[2 * j]);      b := strtoint('$' + hexskey[2 * i - 1] + hexskey[2 * i]);      c := a xor b;      tmpstr := tmpstr + myStrtoHex(chr(c));    end;  end;  result := tmpstr;end;
function decryptstr(const s: string; skey: string): string; //解密var  i, j: integer;  hexS, hexskey, midS, tmpstr: string;  a, b, c: byte;begin  hexS := s; //应该是该字符串  if length(hexS) mod 2 = 1 then  begin    showmessage('密文错误！');    exit;  end;  hexskey := myStrtoHex(skey);  tmpstr := hexS;  midS := hexS;  for i := (length(hexskey) div 2) downto 1 do  begin    if i <> (length(hexskey) div 2) then midS := tmpstr;    tmpstr := '';    for j := 1 to (length(midS) div 2) do    begin      a := strtoint('$' + midS[2 * j - 1] + midS[2 * j]);      b := strtoint('$' + hexskey[2 * i - 1] + hexskey[2 * i]);      c := a xor b;      tmpstr := tmpstr + myStrtoHex(chr(c));    end;  end;  result := myHextoStr(tmpstr);end;

没有一个个去研究，调试。以后在时间在慢慢试。