public void EditBook(Book book, int authorId) { BookValidation validation = new BookValidation(book); validation.BookGeneralValidation.ExecuteValidation(); if (!validation.bookValidationExceptions.Any() && !validation.BookGeneralValidation.generalValidationExceptions.Any()) { _bookDao.EditBook(book, authorId); } else { StringBuilder sb = new StringBuilder(); if (!validation.bookValidationExceptions.Any()) { foreach (var item in validation.bookValidationExceptions) { sb.Append(item + Environment.NewLine); } } if (!validation.BookGeneralValidation.generalValidationExceptions.Any()) { foreach (var item in validation.BookGeneralValidation.generalValidationExceptions) { sb.Append(item + Environment.NewLine); } } throw new BookValidationException(sb.ToString()); } }