private void InitializeTextFinder()
 {
     var extension = Path.GetExtension(_filePath)?.ToLower();
     switch (extension)
     {
         case ".pdf":
             _textFinder = new PdfTextFinder(_filePath, _password);
             break;
         case ".epub":
             _textFinder = new EpubTextFinder(_filePath, _password);
             break;
         default:
             throw new Exception();
     }
 }
        private void InitializeTextFinder()
        {
            var extension = Path.GetExtension(_filePath)?.ToLower();

            switch (extension)
            {
            case ".pdf":
                _textFinder = new PdfTextFinder(_filePath, _password);
                break;

            case ".epub":
                _textFinder = new EpubTextFinder(_filePath, _password);
                break;

            default:
                throw new Exception();
            }
        }