引言: 想請問各位大大 若有一欄位是記錄使用者的密碼 那請問要如何作到加密的功能呢? 因為我有看過有人作過的系統 密碼欄位會出現亂碼 請問要如何作?

 function Encrypt(S: String): String;
var
  i,j,k1,k2: integer;
  cSum,nSum: integer;
  sTmp: String[8];
begin
  Result := Space(8) '??';      //檢查密碼是否合法.
  S := TrimRight(S);
  if Length(S) < 5 then
     begin ShowMsg('密碼長度最少必須5位'); Exit; end;
  if Length(S) > 8 then
     begin ShowMsg('密碼長度超過8位');     Exit; end;
  cSum := 0;
  nSum := 0;
  for i := 1 to Length(S) do begin
    if not (S[i] in ['A'..'Z','a'..'z','0'..'9']) then
       begin ShowMsg('密碼含有不合法字元'); Exit; end;
    if S[i] in ['A'..'Z','a'..'z'] then Inc(cSum);
    if S[i] in ['0'..'9'] then Inc(nSum);
  end;
  if cSum < 3 then
     begin ShowMsg('密碼最少必須含3位字母'); Exit; end;
  if nSum < 2 then
     begin ShowMsg('密碼最少必須含2位數字'); Exit; end;      //加密.
  Randomize;
  while True do begin
    k1 := Random(30);
    k2 := Random(30);
    sTmp := PadR(S,8);
    Result := '';
    for i := 1 to 8 do begin
      j := k1 Mod 30   i;
      j := (k2 j) Mod 30   1;
      Result := Result   Chr(Ord(sTmp[i]) xor j)
    end;
    if (Pos('"',Result)>0) or (Pos('''',Result)>0) then
    Else Break;
  end;
  Result := Result   Chr(k1 40)   Chr(k2 60);
end;

function Decrypt(S: String): String;
var
  i,j: integer;
  Key1,Key2: integer;
begin
  Result := '??' Space(6);      //檢查密碼是否正確.
  if Length(S) <> 10 then Exit;      //解密
  Key1 := Ord(S[9])-40;
  Key2 := Ord(S[10])-60;
  Result := '';
  for i := 1 to 8 do begin
    j := Key1 Mod 30   i;
    j := (Key2 j) Mod 30   1;
    Result := Result   Chr(Ord(S[i]) xor j)
  end;
  Result := Trim(Result);
end;