Select Multiple Files with OpenDialog.

uses ActiveX, ShlObj, ComObj;

function SHMultiFileProperties(pDataObj: IDataObject; Flag: DWORD): HRESULT;

  stdcall; external 'shell32.dll';

function GetFileListDataObject(Files: TStrings): IDataObject;

type

  PArrayOfPItemIDList = ^TArrayOfPItemIDList;

  TArrayOfPItemIDList = array[0..0] of PItemIDList;

var

  Malloc: IMalloc;

  Root: IShellFolder;

  p: PArrayOfPItemIDList;

  chEaten, dwAttributes: ULONG;

  i, FileCount: Integer;

begin

  Result := nil;

  FileCount := Files.Count;

  if FileCount = 0 then Exit;

  OleCheck(SHGetMalloc(Malloc));

  OleCheck(SHGetDesktopFolder(Root));

  p := AllocMem(SizeOf(PItemIDList) * FileCount);

  try

    for i := 0 to FileCount - 1 do

      try

        if not (DirectoryExists(Files[i]) or FileExists(Files[i])) then Continue;

        OleCheck(Root.ParseDisplayName(GetActiveWindow,

          nil,

          PWideChar(WideString(Files[i])),

          chEaten,

          p^[i],

          dwAttributes));

      except

      end;

    OleCheck(Root.GetUIObjectOf(GetActiveWindow,

      FileCount,

      p^[0],

      IDataObject,

      nil,

      Pointer(Result)));

  finally

    for i := 0 to FileCount - 1 do

    begin

      if p^[i] <> nil then Malloc.Free(p^[i]);

    end;

    FreeMem(p);

  end;

end;

procedure ShowFileProperties(Files: TStrings; aWnd: HWND);

type

  PArrayOfPItemIDList = ^TArrayOfPItemIDList;

  TArrayOfPItemIDList = array[0..0] of PItemIDList;

var

  Data: IDataObject;

begin

  if Files.Count = 0 then Exit;

  Data := GetFileListDataObject(Files);

  SHMultiFileProperties(Data, 0);

end;

procedure TForm1.Button1Click(Sender: TObject);

begin

  if OpenDialog1.Execute then

    Memo1.Lines.AddStrings(OpenDialog1.Files);

end;

procedure TForm1.Button2Click(Sender: TObject);

begin

  ShowFileProperties(Memo1.Lines, 0);

end;