Wie nutzt man ein Interface (IKnownFolderManager)

[Uwe Raabe]

Mal abgesehen davon ist die Deklaration von GetFolderIds in ShlObj falsch! Die anderen habe ich jetzt nicht überprüft.

Richtig wäre

Delphi-Quellcode:

    
type
  IKnownFolderManager = interface(IUnknown)
    [SID_IKnownFolderManager]
    function FolderIdFromCsidl(nCsidl: Integer;
      var pfid: TKnownFolderID): HRESULT; stdcall;
    function FolderIdToCsidl(const rfid: TIID;
      var pnCsidl: Integer): HRESULT; stdcall;
    function GetFolderIds(out ppKFId: PGUIDList;
      var pCount: UINT): HRESULT; stdcall;
    function GetFolder(const rfid: TIID;
      out ppkf: IKnownFolder): HRESULT; stdcall;
    function GetFolderByName(pszCanonicalName: LPCWSTR;
      out ppkf: IKnownFolder): HRESULT; stdcall;
    function RegisterFolder(const rfid: TIID;
      var pKFD: TKnownFolderDefinition): HRESULT; stdcall;
    function UnregisterFolder(const rfid: TIID): HRESULT; stdcall;
    function FindFolderFromPath(pszPath: LPCWSTR; mode: FFFP_MODE;
      out ppkf: IKnownFolder): HRESULT; stdcall;
    function FindFolderFromIDList(pidl: PItemIDList;
      out ppkf: IKnownFolder): HRESULT; stdcall;
    function Redirect(const rfid: TIID; hwnd: HWND; flags: TKFRedirectFlags;
      pszTargetPath: LPCWSTR; cFolders: UINT; var pExclusion: TKnownFolderID;
      var ppszError: LPWSTR): HRESULT; stdcall;
  end;

type
  TKnownFolderManager = class
  public
    class function CreateInstance: IKnownFolderManager;
  end;

class function TKnownFolderManager.CreateInstance: IKnownFolderManager;
begin
  if CoCreateInstance(CLSID_KnownFolderManager, nil, CLSCTX_INPROC_SERVER, IID_IKnownFolderManager, Result) <> S_OK then begin
    result := nil;
  end;
end;

procedure TForm254.Button1Click(Sender: TObject);
var
  io : IKnownFolderManager;
  count : Cardinal;
  vielefolder : PGUIDList;
begin
  io:=TKnownFolderManager.CreateInstance;
  io.GetFolderIds(vielefolder, count);
  Memo1.Lines.Add(' Anz:'+inttostr(count));
  CoTaskMemFree(vielefolder);
end;