private void ReadBook()
        {
            switch (_selectedBook.FileType)
            {
            case ".pdf":
                _readersContext = new ReadersContext(new PDFReader());
                _readersContext.Read(_selectedBook.Path);
                break;

            case ".djvu":
                _readersContext = new ReadersContext(new DJVuReader());
                _readersContext.Read(_selectedBook.Path);
                break;
            }
        }
        private void ReadBook()
        {
            if (_selectedBookInCategory == null)
            {
                return;
            }
            switch (_selectedBookInCategory.FileType)
            {
            case ".pdf":
                _readersContext = new ReadersContext(new PDFReader());
                _readersContext.Read(SelectedBookInCategory.Path);
                break;

            case ".djvu":
                _readersContext = new ReadersContext(new DJVuReader());
                _readersContext.Read(_selectedBookInCategory.Path);
                break;
            }
        }