/* 用户书本收藏夹 Begin */
public long AddFavBook(string bookCode, string userId)
{
if (string.IsNullOrEmpty(userId))
{
throw new Exception("非法操作！");
}
return(_userBookRepository.AddUserBook(bookCode, userId).Result);
}
public async Task <Book> CheckoutBook(string username, int bookId)
{
Book book = await _bookRepository.Get(bookId);
if (!book.CheckedOut)
{
book = book.CheckOut(username);
await _repository.AddUserBook(book);
}
return(book);
}