Datei für Schreibzuriffe sperren?

[Christian Seehase]

Moin Thomas,

ich hab' da mal eben was zusammengeschrieben, wie ich mir das so ungefähr vorstelle. Ist natürlich nicht getestet, aber probiers mal aus, bzw. schau's Dir mal an.

Code:

[b]type[/b]
  TcsFileLockEntry =
    [b]packed[/b] [b]record[/b]
      sFilePath : [b]string[/b];
      fsFile    : TFileStream;
    [b]end[/b];

  TcsFileLocker = [b]class[/b](TObject)
  [b]private[/b]
    FaFilelist : [b]array[/b] [b]of[/b] TcsFileLockEntry;
  [b]public[/b]
    [b]constructor[/b] Create;
    [b]destructor[/b] Destroy; override;
    [b]procedure[/b] LockFile([b]const[/b] p_sFilePath : [b]string[/b]);
    [b]procedure[/b] UnlockFile([b]const[/b] p_sFilePath : [b]string[/b]);
  [b]end[/b];

[b]implementation[/b]

[color=#000080]{$R *.DFM}[/color]



[color=#000080]{ TcsFileLocker }[/color]

[b]constructor[/b] TcsFileLocker.Create;
[b]begin[/b]
  [b]inherited[/b] Create;
  [color=#000080]// Nur der Ordung halber, eigentlich nicht notwendig[/color]
  SetLength(FaFileList,0);
[b]end[/b];

[b]destructor[/b] TcsFileLocker.Destroy;

[b]var[/b]
  i : integer;

[b]begin[/b]
  [b]for[/b] i := 0 [b]to[/b] High(FaFileList) [b]do[/b]
  [b]begin[/b]
    FreeAndNil(FaFileList[i].fsFile);
  [b]end[/b];
  SetLength(FaFileList,0);
  [b]inherited[/b] Destroy;
[b]end[/b];

[b]procedure[/b] TcsFileLocker.LockFile([b]const[/b] p_sFilePath: [b]string[/b]);
[b]begin[/b]
  [color=#000080]// Neuen Eintrag erzeugen[/color]
  SetLength(FaFileList,Length(FaFileList)+1);
  FaFileList[High(FaFileList)].sFilePath := p_sFilePath;
  FaFileList[High(FaFileList)].fsFile    := TFileStream.Create(p_sFilePath,fmShareExclusive);
[b]end[/b];

[b]procedure[/b] TcsFileLocker.UnlockFile([b]const[/b] p_sFilePath: [b]string[/b]);

[b]var[/b]
  i        : integer;
  iDeleted : integer;

[b]begin[/b]
  iDeleted := -1;
  [b]for[/b] i := 0 [b]to[/b] High(FaFileList) [b]do[/b]
  [b]begin[/b]
    [b]if[/b] FaFileList[i].sFilePath = p_sFilePath [b]then[/b]
    [b]begin[/b]
      FreeAndNil(FaFileList[i].fsFile);
      iDeleted := i;
      break;
    [b]end[/b];
  [b]end[/b];
  [b]if[/b] iDeleted > -1 [b]then[/b]
  [b]begin[/b]
    [b]for[/b] i := iDeleted+1 [b]to[/b] High(FaFileList) [b]do[/b]
    [b]begin[/b]
      FaFileList[i-1] := FaFileList[i];
    [b]end[/b];
    SetLength(FaFileList,Length(FaFileList)-1);
  [b]end[/b];
[b]end[/b];