public async Task UpdateAsync(long id, BookRequestDto dto)
{
dto.Sanitize();
var book = await _bookRepository.GetByIdAsync(id,
q => q.Include(x => x.BookTags).Include(x => x.Links));
Mapper.Map(dto, book);
// 处理标签，先移除标签与图书的关联再添加
Context.RemoveRange(book.BookTags);
foreach (var tname in dto.Tags)
{
var tag = await _tagRepository.GetByName(tname);
if (tag == null)
{
tag = new Tag()
{
Name = tname
}
}
;
book.BookTags.Add(new BookTag {
Book = book, Tag = tag
});
}
// 处理下载链接，移除已删除项
var oldLinks = await _linkRepository.GetByBookIdAsync(id);
foreach (var oldLink in oldLinks)
{
if (!book.Links.Any(x => x.Id == oldLink.Id))
{
Context.Remove(oldLink);
}
}
await Context.SaveChangesAsync();
}