CRC32 DEC 5

[r4id3n]

Hi, leider habe ich einige Probleme ... Leider erhalte ich einen anderen CRC als meine Ursprungsversion, sicherlich für Dich nur eine kleinigkeit....

Implementiert habe ich das ganze jetzt so:

Delphi-Quellcode:

function GetCRC32(FileName:String):String;
var     F:TFileStream;
        CRC:Cardinal;
        OldCRC:string;
begin
        F:=TFileStream.Create(FileName,fmOpenRead);
        try
                CRC:=CRCCalcEx(CRC_32CCITT,F.Read);
        finally
                F.Free;
        end;
        result:='$' + IntToHex(CRC,2);
        OldCRC:=CRCOld.GetCRC32Old(FileName);
        if result = OldCRC then
                beep;
end;

Die CRCOld sieht so aus:

Delphi-Quellcode:

unit CRCOld;

interface

procedure BuildCRCTable;
function RecountCRC(b: byte; CrcOld: Longint): Longint;
function HextW(w: Word): string;
function HextL(l: Longint): string;
function GetCRC32Old(FileName: string): string;

implementation

type
  Long = record
    LoWord: Word;
    HiWord: Word;
  end;

const
  CRCPOLY = $EDB88320;

var
  CRCTable: array[0..512] Of Longint;

procedure BuildCRCTable;
var
  i, j: Word;
  r: Longint;
begin
  FillChar(CRCTable, SizeOf(CRCTable), 0);
  for i := 0 to 255 do
  begin
    r := i shl 1;
    for j := 8 downto 0 do
      if (r and 1) <> 0 then
        r := (r Shr 1) xor CRCPOLY
      else
        r := r shr 1;
    CRCTable[i] := r;
   end;
end;

function RecountCRC(b: byte; CrcOld: Longint): Longint;
begin
  RecountCRC := CRCTable[byte(CrcOld xor Longint(b))] xor ((CrcOld shr 8) and $00FFFFFF)
end;

function HextW(w: Word): string;
const
  h: array[0..15] Of char = '0123456789ABCDEF';
begin
  HextW := '';
  HextW := h[Hi(w) shr 4] + h[Hi(w) and $F] + h[Lo(w) shr 4]+h[Lo(w) and $F];
end;

function HextL(l: Longint): string;
begin
  with Long(l) do
    HextL := HextW(HiWord) + HextW(LoWord);
end;

function GetCRC32Old(FileName: string): string;
var
  Buffer: PChar;
  f: File of Byte;
  b: array[0..255] of Byte;
  CRC: Longint;
  e, i: Integer;
begin
  BuildCRCTable;
  CRC := $FFFFFFFF;
  AssignFile(F, FileName);
  FileMode := 0;
  Reset(F);
  GetMem(Buffer, SizeOf(B));
  repeat
    FillChar(b, SizeOf(b), 0);
    BlockRead(F, b, SizeOf(b), e);
    for i := 0 to (e-1) do
     CRC := RecountCRC(b[i], CRC);
  until (e < 255) or (IOresult <> 0);
  FreeMem(Buffer, SizeOf(B));
  CloseFile(F);
  CRC := Not CRC;
  Result := '$' + HextL(CRC);
end;
end.

Wo liegt der Fehler?
P.S: Den Type

Delphi-Quellcode:

type
  TReadMethod = function(var Buffer; Count: LongInt): LongInd of object;

musste ich auf

Delphi-Quellcode:

type
  TReadMethod = function(var Buffer; Count: Integer): Integer of object;

ändern, da sonst die Read-Funktion einen Type mismatch brachte!!

10000000000 fach dank für Deine Hilfe!!!