public async Task DeleteGroupAsync(EntityDto <long> input) { var isSystemGroup = Enum.IsDefined(typeof(DefaultGroups), (int)input.Id); if (isSystemGroup) { throw new UserFriendlyException("PictureGallery.Group.SystemGroup.CantNotDelete"); } var pictureGroup = await _pictureManager.GetGroupByIdAsync(input.Id); //无法删除系统分组 if (pictureGroup.IsSystemGroup) { throw new UserFriendlyException("PictureGallery.Group.SystemGroup.CantNotDelete"); } var pictures = await _pictureManager.Pictures.Where(p => p.GroupId == pictureGroup.Id).ToListAsync(); pictures.Each(t => t.GroupId = 0); await _pictureManager.DeleteGroupAsync(pictureGroup); }