用delphi实现qq在Web登录的密码客户端加密功能.

使用到TIdHashMessageDigest5. uses IdHashMessageDigest; function Preprocess(aPassWord, aVerifyCode:string):string;
begin
     Result:= Fmd5(md5_3(aPassWord) + UpperCase(aVerifyCode));
end; function md5_3(str:string):string;
begin
     Result:= Fmd5(str);
     Result:= HashStr2BinStr(Result);
     Result:= Fmd5(Result);
     Result:= HashStr2BinStr(Result);
     Result:= Fmd5(Result);
end; function Fmd5(str:string):string;
var
   md5 : TIdHashMessageDigest5;
   longWordRec : T4x4LongWordRecord;
begin
     md5 := TIdHashMessageDigest5.Create;
     try
        {$IFDEF ID10}
        Result:= md5.HashStringAsHex(str);
        {$ELSE}
        longWordRec:= md5.HashValue(str);
        Result:= md5.AsHex(longWordRec);
        {$ENDIF}
     finally
        md5.Free;
     end;
end; function HashStr2BinStr(Hash:string):string;
var
   buf:array[0..63] of Char;
   i:Integer;
begin
    Result:='';
    FillChar(buf, SizeOf(buf),0);
    SetLength(Result, Round(Length(Hash)/2));
    FillChar(Result[1], Length(Result),0);
    HexToBin(PChar(Hash), buf,SizeOf(buf));
    for i:=0 to Round(Length(Hash)/2)-1 do
        Result:= buf;
end;     使用方法： 密码和验证码加密后的结果 = Preprocess